Статті в журналах: "Biotin transporter; Staphylococcus aureus"

1

Erba, Paola Anna, Angela G. Cataldi, Carlo Tascini, Alessandro Leonildi, Chiara Manfredi, Giuliano Mariani, and Elena Lazzeri. "111In-DTPA-Biotin uptake by Staphylococcus aureus." Nuclear Medicine Communications 31, no. 11 (November 2010): 994–97. http://dx.doi.org/10.1097/mnm.0b013e32833ce32c.

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2

Hayes, Andrew J., Jiulia Satiaputra, Louise M. Sternicki, Ashleigh S. Paparella, Zikai Feng, Kwang J. Lee, Beatriz Blanco-Rodriguez, et al. "Advanced Resistance Studies Identify Two Discrete Mechanisms in Staphylococcus aureus to Overcome Antibacterial Compounds that Target Biotin Protein Ligase." Antibiotics 9, no. 4 (April 6, 2020): 165. http://dx.doi.org/10.3390/antibiotics9040165.

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Biotin protein ligase (BPL) inhibitors are a novel class of antibacterial that target clinically important methicillin-resistant Staphylococcus aureus (S. aureus). In S. aureus, BPL is a bifunctional protein responsible for enzymatic biotinylation of two biotin-dependent enzymes, as well as serving as a transcriptional repressor that controls biotin synthesis and import. In this report, we investigate the mechanisms of action and resistance for a potent anti-BPL, an antibacterial compound, biotinyl-acylsulfamide adenosine (BASA). We show that BASA acts by both inhibiting the enzymatic activity of BPL in vitro, as well as functioning as a transcription co-repressor. A low spontaneous resistance rate was measured for the compound (<10−9) and whole-genome sequencing of strains evolved during serial passaging in the presence of BASA identified two discrete resistance mechanisms. In the first, deletion of the biotin-dependent enzyme pyruvate carboxylase is proposed to prioritize the utilization of bioavailable biotin for the essential enzyme acetyl-CoA carboxylase. In the second, a D200E missense mutation in BPL reduced DNA binding in vitro and transcriptional repression in vivo. We propose that this second resistance mechanism promotes bioavailability of biotin by derepressing its synthesis and import, such that free biotin may outcompete the inhibitor for binding BPL. This study provides new insights into the molecular mechanisms governing antibacterial activity and resistance of BPL inhibitors in S. aureus.

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3

Satiaputra, Jiulia, Bart A. Eijkelkamp, Christopher A. McDevitt, Keith E. Shearwin, Grant W. Booker, and Steven W. Polyak. "Biotin-mediated growth and gene expression in Staphylococcus aureus is highly responsive to environmental biotin." Applied Microbiology and Biotechnology 102, no. 8 (March 5, 2018): 3793–803. http://dx.doi.org/10.1007/s00253-018-8866-z.

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4

Schrader-Fischer, Gesine, and Brigitte Berger-Bächi. "The AbcA Transporter of Staphylococcus aureus Affects Cell Autolysis." Antimicrobial Agents and Chemotherapy 45, no. 2 (February 1, 2001): 407–12. http://dx.doi.org/10.1128/aac.45.2.407-412.2001.

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ABSTRACT Increased production of penicillin-binding protein PBP 4 is known to increase peptidoglycan cross-linking and contributes to methicillin resistance in Staphylococcus aureus. The pbp4gene shares a 400-nucleotide intercistronic region with the divergently transcribed abcA gene, encoding an ATP-binding cassette transporter of unknown function. Our study revealed that methicillin stimulated abcA transcription but had no effects onpbp4 transcription. Analysis of abcA expression in mutants defective for global regulators showed that abcAis under the control of agr. Insertional inactivation ofabcA by an erythromycin resistance determinant did not influence pbp4 transcription, nor did it alter resistance to methicillin and other cell wall-directed antibiotics. However,abcA mutants showed spontaneous partial lysis on plates containing subinhibitory concentrations of methicillin due to increased spontaneous autolysis. Since the autolytic zymograms of cell extracts were identical in mutants and parental strains, we postulate an indirect role of AbcA in control of autolytic activities and in protection of the cells against methicillin.

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5

Huang, Jianzhong, Paul W. O'Toole, Wei Shen, Heather Amrine-Madsen, Xinhe Jiang, Neethan Lobo, Leslie M. Palmer, et al. "Novel Chromosomally Encoded Multidrug Efflux Transporter MdeA in Staphylococcus aureus." Antimicrobial Agents and Chemotherapy 48, no. 3 (March 2004): 909–17. http://dx.doi.org/10.1128/aac.48.3.909-917.2004.

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ABSTRACT Antibiotic efflux is an important mechanism of resistance in pathogenic bacteria. Here we describe the identification and characterization of a novel chromosomally encoded multidrug resistance efflux protein in Staphylococcus aureus, MdeA (multidrug efflux A). MdeA was identified from screening an S. aureus open reading frame expression library for resistance to antibiotic compounds. When overexpressed, MdeA confers resistance on S. aureus to a range of quaternary ammonium compounds and antibiotics, but not fluoroquinolones. MdeA is a 52-kDa protein with 14 predicted transmembrane segments. It belongs to the major facilitator superfamily and is most closely related, among known efflux proteins, to LmrB of Bacillus subtilis and EmrB of Escherichia coli. Overexpression of mdeA in S. aureus reduced ethidium bromide uptake and enhanced its efflux, which could be inhibited by reserpine and abolished by an uncoupler. The mdeA promoter was identified by primer extension. Spontaneous mutants selected for increased resistance to an MdeA substrate had undergone mutations in the promoter for mdeA, and their mdeA transcription levels were increased by as much as 15-fold. The mdeA gene was present in the genomes of all six strains of S. aureus examined. Uncharacterized homologs of MdeA were present elsewhere in the S. aureus genome, but their overexpression did not mediate resistance to the antibacterials tested. However, MdeA homologs were identified in other bacteria, including Bacillus anthracis, some of which were shown to be functional orthologs of MdeA.

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6

Tieu, William, Angie M. Jarrad, Ashleigh S. Paparella, Kelly A. Keeling, Tatiana P. Soares da Costa, John C. Wallace, Grant W. Booker, Steven W. Polyak, and Andrew D. Abell. "Heterocyclic acyl-phosphate bioisostere-based inhibitors of Staphylococcus aureus biotin protein ligase." Bioorganic & Medicinal Chemistry Letters 24, no. 19 (October 2014): 4689–93. http://dx.doi.org/10.1016/j.bmcl.2014.08.030.

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7

Huggins, Luke G., Kathryn D. Robinson, Kyra P. Lasko, Lauren B. Clower, Avery J. Gookin, Dustin E. Segraves, James C. Gainer, Grant P. Basagic, Kelly R. Machuca, and Jacobo Rendon. "Screening for community-acquired strains of methicillinresistant Staphylococcus aureus susceptible to extracts of Centaurea nigrescens." Journal of Phytopharmacology 7, no. 3 (June 29, 2018): 298–304. http://dx.doi.org/10.31254/phyto.2018.7312.

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The rates of infection by community-acquired multi-drug resistant Staphylococcus aureus have risen dramatically over fifteen years in the United States. Community-acquired multi-drug resistant Staphylococcus aureus is responsible for rapidly progressive diseases, including necrotizing pneumonia, severe sepsis, and necrotizing fasciitis. Consequently, novel antibacterial strategies are needed to combat the rising antibiotic resistance seen in community-acquired multi-drug resistant strains. We have screened the Nebraska Transposon Mutant Library for MRSA strains that are either susceptible or resistant to methanol extracts of Centaurea nigrescens leaves and flowers. 10 strains containing mutations affecting transporter proteins were identified as having either significant resistance or susceptibility to Centaurea extract. Insertions in two different drug efflux transporter families have been identified. The EmrB/QacA drug resistance transporter subfamily is a multi-drug efflux pump responsible for the export of toxic molecules from bacteria and yeast. The ABC transporters are involved in drug import and export. These results confirm the effectiveness of the screen as a means for identifying drug-resistance genes affected by the C. nigrescens methanolic extract and suggest a role for drug efflux proteins in the resistance of S. aureus community-acquired multi-drug resistant Staphylococcus aureus to antibacterial plant metabolites

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8

Markham, Penelope N., Eric Westhaus, Katya Klyachko, Michael E. Johnson, and Alex A. Neyfakh. "Multiple Novel Inhibitors of the NorA Multidrug Transporter of Staphylococcus aureus." Antimicrobial Agents and Chemotherapy 43, no. 10 (October 1, 1999): 2404–8. http://dx.doi.org/10.1128/aac.43.10.2404.

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ABSTRACT The multidrug transporter NorA contributes to the resistance ofStaphylococcus aureus to fluoroquinolone antibiotics by promoting their active extrusion from the cell. Previous studies with the alkaloid reserpine, the first identified inhibitor of NorA, indicate that the combination of a chemical NorA inhibitor with a fluoroquinolone could improve the efficacy of this class of antibiotics. Since reserpine is toxic to humans at the concentrations required to inhibit NorA, we sought to identify new inhibitors of NorA that may be used in a clinical setting. Screening of a chemical library yielded a number of structurally diverse inhibitors of NorA that were more potent than reserpine. The new inhibitors act in a synergistic manner with the most widely used fluoroquinolone, ciprofloxacin, by substantially increasing its activity against both NorA-overexpressing and wild-type S. aureus isolates. Furthermore, the inhibitors dramatically suppress the emergence of ciprofloxacin-resistant S. aureus upon in vitro selection with this drug. Some of these new inhibitors, or their derivatives, may prove useful for augmentation of the antibacterial activities of fluoroquinolones in the clinical setting.

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9

Morrissey, Julie A., Alan Cockayne, Philip J. Hill, and Paul Williams. "Molecular Cloning and Analysis of a Putative Siderophore ABC Transporter from Staphylococcus aureus." Infection and Immunity 68, no. 11 (November 1, 2000): 6281–88. http://dx.doi.org/10.1128/iai.68.11.6281-6288.2000.

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ABSTRACT From a mass-excised Staphylococcus aureus λZapII expression library, we cloned an operon encoding a novel ABC transporter with significant homology to bacterial siderophore transporter systems. The operon encodes four genes designatedsstA, -B, -C, and -Dencoding two putative cytoplasmic membrane proteins (sstAand sstB), an ATPase (sstC), and a membrane-bound 38-kDa lipoprotein (sstD). Thesst operon is preceded by two putative Fur boxes, which indicated that expression of the sst operon was likely to be iron dependent. SstD was overexpressed inEscherichia coli, purified by Triton X-114 phase partitioning, and used to generate monospecific antisera in rats. Immunoblotting studies located SstD in the membrane fraction ofS. aureus and showed that expression of the lipoprotein was reduced under iron-rich growth conditions. Triton X-114 partitioning studies on isolated membranes provided additional biochemical evidence that SstD in S. aureus is a lipoprotein. Immunoreactive polypeptides of approximately 38 kDa were detected in a wide range of staphylococcal species, but no antigenic homolog was detected inBacillus subtilis. Expression of SstD in vivo was confirmed by immunoblotting studies with S. aureus recovered from a rat intraperitoneal chamber implant model. To further define the contribution of SstD in promoting growth of S. aureus in vitro and in vivo, we used antisense RNA technology to modulate expression of SstD. Expression of antisense sstD RNA inS. aureus resulted in a decrease in SstD expression under both iron-rich and iron-restricted growth conditions. However, this reduction in SstD levels did not affect the growth of S. aureus in vitro in an iron-limited growth medium or when grown in an intraperitoneal rat chamber implant model in vivo.

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10

Paparella, Ashleigh S., Kwang Jun Lee, Andrew J. Hayes, Jiage Feng, Zikai Feng, Danielle Cini, Sonali Deshmukh, et al. "Halogenation of Biotin Protein Ligase Inhibitors Improves Whole Cell Activity against Staphylococcus aureus." ACS Infectious Diseases 4, no. 2 (November 16, 2017): 175–84. http://dx.doi.org/10.1021/acsinfecdis.7b00134.

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11

Kiran, Madanahally D., Donna E. Akiyoshi, Andrea Giacometti, Oscar Cirioni, Giorgio Scalise, and Naomi Balaban. "OpuC – an ABC Transporter that is Associated with Staphylococcus Aureus Pathogenesis." International Journal of Artificial Organs 32, no. 9 (September 2009): 600–610. http://dx.doi.org/10.1177/039139880903200909.

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RIP is a novel antibiotic against staphylococci. It acts at least in part by competing with RNAIII activating protein (RAP) by downregulating TRAP histidine phosphorylation, and by downregulating the expression of the Acessory Gene Regulator (agr). While much is known about the function of the agr as a quorum sensing system that regulates virulence, not much is known about TRAP. TRAP is a 167-kDa protein that is highly conserved among staphylococci and is involved in DNA protection from stress. TRAP is membrane-associated but does not have a transmembrane domain, and thus it may be bound to the membrane through other proteins. To search for these proteins, protein-protein interaction studies were carried out using a bacterial two-hybrid system, and OpuCA was discovered as a TRAP-binding protein. OpuCA is an ATP binding-cytoplasmic (ABC) domain of an OpuC ABC transporter. S. aureus OpuC– mutant strain was constructed and shown to be less tolerant to salt stress, and was defective in choline uptake. OpuC– cells were less pathogenic and showed reduced TRAP phosphorylation and agr activity, did not respond to RAP, and were defective in biofilm formation in vitro and in vivo. These results suggest that OpuC acts as a transporter and also plays a role in S. aureus pathogenesis.

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12

Rahman, Md Arifur, Ardeshir Amirkhani, Durdana Chowdhury, Maria Mempin, Mark P. Molloy, Anand Kumar Deva, Karen Vickery, and Honghua Hu. "Proteome of Staphylococcus aureus Biofilm Changes Significantly with Aging." International Journal of Molecular Sciences 23, no. 12 (June 8, 2022): 6415. http://dx.doi.org/10.3390/ijms23126415.

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Staphylococcus aureus is a notorious biofilm-producing pathogen that is frequently isolated from implantable medical device infections. As biofilm ages, it becomes more tolerant to antimicrobial treatment leading to treatment failure and necessitating the costly removal of infected devices. In this study, we performed in-solution digestion followed by TMT-based high-throughput mass spectrometry and investigated what changes occur in the proteome of S. aureus biofilm grown for 3-days and 12-days in comparison with 24 h planktonic. It showed that proteins associated with biosynthetic processes, ABC transporter pathway, virulence proteins, and shikimate kinase pathway were significantly upregulated in a 3-day biofilm, while proteins associated with sugar transporter, degradation, and stress response were downregulated. Interestingly, in a 3-day biofilm, we observed numerous proteins involved in the central metabolism pathways which could lead to biofilm growth under diverse environments by providing an alternative metabolic route to utilize energy. In 12-day biofilms, proteins associated with peptidoglycan biosynthesis, sugar transporters, and stress responses were upregulated, whereas proteins associated with ABC transporters, DNA replication, and adhesion proteins were downregulated. Gene Ontology analysis revealed that more proteins are involved in metabolic processes in 3dwb compared with 12dwb. Furthermore, we observed significant variations in the formation of biofilms resulting from changes in the level of metabolic activity in the different growth modes of biofilms that could be a significant factor in S. aureus biofilm maturation and persistence. Collectively, potential marker proteins were identified and further characterized to understand their exact role in S. aureus biofilm development, which may shed light on possible new therapeutic regimes in the treatment of biofilm-related implant-associated infections.

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13

Henze, U. U., and B. Berger-Bächi. "Penicillin-binding protein 4 overproduction increases beta-lactam resistance in Staphylococcus aureus." Antimicrobial Agents and Chemotherapy 40, no. 9 (September 1996): 2121–25. http://dx.doi.org/10.1128/aac.40.9.2121.

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The Staphylococcus aureus mutant strain PVI selected in vitro for methicillin resistance overexpressed penicillin-binding protein (PBP) 4. In the wild-type parent strain the pbp4 gene was separated by 419 nucleotides from a divergently transcribed abcA locus coding for an ATP-binding cassette transporter. The mutant PVI was shown to have a deletion in the pbp4-abcA promoter region that affected pbp4 transcription but not expression of abcA. Introduction of the pbp4 gene plus the mutant promoter region into different genetic backgrounds revealed that PBP 4 overproduction was sufficient to increase in vitro-acquired methicillin resistance independently of other chromosomal genes. The role of the AbcA transporter in methicillin resistance remained unknown.

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14

Morioka, H., A. Suganuma, and M. Tachibana. "Localization of sugar-binding sites in Staphylococcus aureus using gold-labeled neoglycoprotein." Journal of Histochemistry & Cytochemistry 42, no. 12 (December 1994): 1609–13. http://dx.doi.org/10.1177/42.12.7983361.

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We studied post- and pre-embedding staining of sugar-binding sites on thin sections of Staphylococcus aureus with an electron microscopic neoglycoprotein-gold technique. Although gold particles of cellobiosyl bovine serum albumin (BSA)-glycosylated BSA-, lactosyl BSA-, and melibiosyl BSA-gold did not label, heavy labeling of N-acetylglucosaminide-BSA-gold was observed in both the cell wall and the cytoplasm on Spurr-embedded thin sections of S. aureus. Inhibition of labeling with wheat germ agglutinin-biotin and N-acetylglucosaminidase indicated that the labeling was due to N-acetylglucosamine. These data suggested that molecules that bind specifically with N-acetylglucosamine occur in the cell wall and cytoplasm of S. aureus. Pre-embedding staining revealed that these molecules are abundant at the surface of the cell wall and that the abundance differs depending on the bacterial strain. An N-acetylglucosamine-specific lectin-like substance, glucosaminidase, and toxins are proposed as candidates for molecules responsible for the labeling, and the possible functional significance of the findings is discussed briefly.

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15

Zeytuni, N., S. W. Dickey, J. Hu, H. T. Chou, L. J. Worrall, J. A. N. Alexander, M. L. Carlson, et al. "Structural insight into the Staphylococcus aureus ATP-driven exporter of virulent peptide toxins." Science Advances 6, no. 40 (September 2020): eabb8219. http://dx.doi.org/10.1126/sciadv.abb8219.

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Staphylococcus aureus is a major human pathogen that has acquired alarming broad-spectrum antibiotic resistance. One group of secreted toxins with key roles during infection is the phenol-soluble modulins (PSMs). PSMs are amphipathic, membrane-destructive cytolytic peptides that are exported to the host-cell environment by a designated adenosine 5′-triphosphate (ATP)–binding cassette (ABC) transporter, the PSM transporter (PmtABCD). Here, we demonstrate that the minimal Pmt unit necessary for PSM export is PmtCD and provide its first atomic characterization by single-particle cryo-EM and x-ray crystallography. We have captured the transporter in the ATP-bound state at near atomic resolution, revealing a type II ABC exporter fold, with an additional cytosolic domain. Comparison to a lower-resolution nucleotide-free map displaying an “open” conformation and putative hydrophobic inner chamber of a size able to accommodate the binding of two PSM peptides provides mechanistic insight and sets the foundation for therapeutic design.

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16

Hall, Jason A., and Ana M. Pajor. "Functional Characterization of a Na+-Coupled Dicarboxylate Carrier Protein from Staphylococcus aureus." Journal of Bacteriology 187, no. 15 (August 1, 2005): 5189–94. http://dx.doi.org/10.1128/jb.187.15.5189-5194.2005.

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ABSTRACT We have cloned and functionally characterized a Na+-coupled dicarboxylate transporter, SdcS, from Staphylococcus aureus. This carrier protein is a member of the divalent anion/Na+ symporter (DASS) family and shares significant sequence homology with the mammalian Na+/dicarboxylate cotransporters NaDC-1 and NaDC-3. Analysis of SdcS function indicates transport properties consistent with those of its eukaryotic counterparts. Thus, SdcS facilitates the transport of the dicarboxylates fumarate, malate, and succinate across the cytoplasmic membrane in a Na+-dependent manner. Furthermore, kinetic work predicts an ordered reaction sequence with Na+ (K 0.5 of 2.7 mM) binding before dicarboxylate (Km of 4.5 μM). Because this transporter and its mammalian homologs are functionally similar, we suggest that SdcS may serve as a useful model for DASS family structural analysis.

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17

Pendini, Nicole R., Min Y. Yap, Steven W. Polyak, Nathan P. Cowieson, Andrew Abell, Grant W. Booker, John C. Wallace, Jacqueline A. Wilce, and Matthew C. J. Wilce. "Structural characterisation of Staphylococcus aureus biotin protein ligase and interaction partners: An antibiotic target." Protein Science 23, no. 1 (December 19, 2013): 121. http://dx.doi.org/10.1002/pro.2399.

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18

Needham, Andrew J., Monica Kibart, Howard Crossley, Philip W. Ingham, and Simon J. Foster. "Drosophila melanogaster as a model host for Staphylococcus aureus infection." Microbiology 150, no. 7 (July 1, 2004): 2347–55. http://dx.doi.org/10.1099/mic.0.27116-0.

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Staphylococcus aureus is an important pathogen of humans, causing a range of superficial and potentially life-threatening diseases. Infection of the fruit fly Drosophila melanogaster with S. aureus results in systemic infection followed by death. Screening of defined S. aureus mutants for components important in pathogenesis identified perR and pheP, with fly death up to threefold slower after infection with the respective mutants compared to the wild-type. Infection of D. melanogaster with reporter gene fusion strains demonstrated the in vivo expression levels of the accessory gene regulator, agr, α-toxin, hla, and a manganese transporter, mntA. The use of the green fluorescent protein as a reporter under the control of the agr promoter (P3) showed S. aureus microcolony formation in vivo. The disease model also allowed the effect of antibiotic treatment on the flies to be determined. D. melanogaster is a genetically tractable model host for high-throughput analysis of S. aureus virulence determinants.

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19

Neyfakh, A. A., C. M. Borsch, and G. W. Kaatz. "Fluoroquinolone resistance protein NorA of Staphylococcus aureus is a multidrug efflux transporter." Antimicrobial Agents and Chemotherapy 37, no. 1 (January 1, 1993): 128–29. http://dx.doi.org/10.1128/aac.37.1.128.

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20

Cabrera, Guillermo, Anming Xiong, Michelle Uebel, Vineet K. Singh, and Radheshyam K. Jayaswal. "Molecular Characterization of the Iron-Hydroxamate Uptake System in Staphylococcus aureus." Applied and Environmental Microbiology 67, no. 2 (February 1, 2001): 1001–3. http://dx.doi.org/10.1128/aem.67.2.1001-1003.2001.

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ABSTRACT To investigate iron uptake, a chromosomal locus containing three consecutive open reading frames, designated fhuC,fhuB, and fhuD, was identified inStaphylococcus aureus. Whereas the fhuC gene encodes an ATP-binding protein, fhuB and fhuDcode for ferrichrome permeases and thus resemble an ATP-binding cassette transporter. A fhuB knockout mutant showed impaired uptake of iron bound to the siderophores but not of ferric chloride, suggesting that this operon is specific for siderophore-mediated iron uptake.

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21

Wang, Yutong, Zhengzheng Wang, Zhongxu Zhan, Leina Yan, Lijun Wang, and Hengyi Xu. "Sensitive Detection of Staphylococcus aureus by a Colorimetric Biosensor Based on Magnetic Separation and Rolling Circle Amplification." Foods 11, no. 13 (June 23, 2022): 1852. http://dx.doi.org/10.3390/foods11131852.

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Staphylococcus aureus (S. aureus) is a common foodborne pathogen that causes fever, vomiting, and other intestinal symptoms, and seriously affects human health and social safety. As a result, a reliable and sensitive detection technique for S. aureus must be developed. In this work, we proposed a sandwich assay on vancomycin functionalized magnetic beads (Van-MNPs) for S. aureus detection based on the specific binding between IgG and targets. The Van-MNPs were used as a tool for the separation of target bacteria. The biotin-modified IgG mediates binding between DNA nanoflowers (DNFs) and the target bacteria via interacting with streptavidin. The DNFs prepared by rolling circle amplification (RCA) were employed as a nano-container to enhance the capacity of biotins, and the streptavidin-horseradish peroxidase (SA-HRP) was loaded onto DNFs to catalyze the color change of TMB. Therefore, a colorimetric biosensor based on magnetic separation and rolling circle amplification was developed. The proposed methods for S. aureus detection showed a limit of detection (LOD) of 3.3 × 103 CFU/mL and excellent specificity. The biosensor has a certain reference value for the detection of S. aureus in juice.

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22

Burnie, James P., Ruth C. Matthews, Tracey Carter, Elaine Beaulieu, Michael Donohoe, Caroline Chapman, Peter Williamson, and Samantha J. Hodgetts. "Identification of an Immunodominant ABC Transporter in Methicillin-Resistant Staphylococcus aureusInfections." Infection and Immunity 68, no. 6 (June 1, 2000): 3200–3209. http://dx.doi.org/10.1128/iai.68.6.3200-3209.2000.

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ABSTRACT Immunoblotting sera from 26 patients with septicemia due to an epidemic strain of methicillin-resistant Staphylococcus aureus (EMRSA-15), 6 of whom died, revealed an immunodominant EMRSA-15 antigen at 61 kDa. There was a statistically significant correlate (P < 0.001) between survival and immunoglobulin G to the 61-kDa band. The antigen was identified by sequencing positive clones obtained by screening a genomic expression library of EMRSA-15 with pooled sera from patients taken after the septicemic episode. Eluted antibody reacted with the 61-kDa antigen on immunoblots. The amino terminus was obtained by searching the S. aureus NCTC 8325 and MRSA strain COL databases, and the whole protein was expressed in Escherichia coli TOP 10F′. The derived amino acid sequence showed homology with ABC transporters, with paired Walker A and Walker B motifs and 73% homology to YkpA fromBacillus subtilis. Epitope mapping of the derived amino acid sequence with sera from patients who had recovered from EMRSA-15 septicemia delineated seven epitopes. Three of these epitopes, represented by peptides 1 (KIKVYVGNYDFWYQS), 2 (TVIVVSHDRHFLYNNV), and 3 (TETFLRGFLGRMLFS), were synthesized and used to isolate human recombinant antibodies from a phage antibody display library. Recombinant antibodies against peptides 1 and 2 gave logarithmic reductions in organ colony counts, compared with control groups, in a mouse model of the infection. This study suggests the potential role of an ABC transporter as a target for immunotherapy.

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23

Paparella, Ashleigh S., Jiage Feng, Beatriz Blanco-Rodriguez, Zikai Feng, Wanida Phetsang, Mark A. T. Blaskovich, Matthew A. Cooper, Grant W. Booker, Steven W. Polyak, and Andrew D. Abell. "A template guided approach to generating cell permeable inhibitors of Staphylococcus aureus biotin protein ligase." Tetrahedron 74, no. 12 (March 2018): 1175–83. http://dx.doi.org/10.1016/j.tet.2017.10.032.

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24

Yu, Linda P. C., Chi-Yuan Chou, Philip H. Choi, and Liang Tong. "Characterizing the Importance of the Biotin Carboxylase Domain Dimer for Staphylococcus aureus Pyruvate Carboxylase Catalysis." Biochemistry 52, no. 3 (January 9, 2013): 488–96. http://dx.doi.org/10.1021/bi301294d.

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25

Reddy, Prakash Narayana, Sowmya Nagaraj, Murali H. Sripathy, and Harsh Vardhan Batra. "Use of biotin-labeled IgY overcomes protein A interference in immunoassays involving Staphylococcus aureus antigens." Annals of Microbiology 65, no. 4 (January 17, 2015): 1915–22. http://dx.doi.org/10.1007/s13213-014-1029-2.

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26

Truong-Bolduc, Q. C., P. M. Dunman, T. Eidem, and D. C. Hooper. "Transcriptional Profiling Analysis of the Global Regulator NorG, a GntR-Like Protein of Staphylococcus aureus." Journal of Bacteriology 193, no. 22 (September 9, 2011): 6207–14. http://dx.doi.org/10.1128/jb.05847-11.

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The GntR-like protein NorG has been shown to affectStaphylococcus aureusgenes involved in resistance to quinolones and β-lactams, such as those encoding the NorB and AbcA transporters. To identify the target genes regulated by NorG, we carried out transcriptional-profiling assays usingS. aureusRN6390 and its isogenicnorG::catmutant. Our data showed that NorG positively affected the transcription of global regulatorsmgrA,arlS, andsarZ. The three putative drug efflux pump genes most positively affected by NorG were the NorB efflux pump (5.1-fold), the MmpL-like protein SACOL2566 (5.2-fold), and the BcrA-like drug transporter SACOL2525 (5.7-fold) genes. TheS. aureuspredicted MmpL protein showed 53% homology with the MmpL lipid transporter ofMycobacterium tuberculosis, and the putative SACOL2525 protein showed 87% homology with the bacitracin drug transporter BcrA ofStaphylococcus hominis. Two pump genes most negatively affected by NorG were the NorC (4-fold) and AbcA (6-fold) genes. Other categories of genes, such as those participating in amino acid, inorganic ion, or nucleotide transporters and metabolism, were also affected by NorG. Real-time reverse transcription (RT)-PCR assays formgrA,arlS,sarZ,norB,norC,abcA,mmpL, andbcrA-like were carried out to verify microarray data and showed the same level of up- or downregulation by NorG. ThenorGmutant showed a 2-fold increase in resistance to norfloxacin and rhodamine, both substrates of the NorC transporter, which is consistent with the resistance phenotype conferred by overexpression ofnorCon a plasmid. These data indicate that NorG has broad regulatory function inS. aureus.

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Dale, Suzanne E., M. Tom Sebulsky, and David E. Heinrichs. "Involvement of SirABC in Iron-Siderophore Import in Staphylococcus aureus." Journal of Bacteriology 186, no. 24 (December 15, 2004): 8356–62. http://dx.doi.org/10.1128/jb.186.24.8356-8362.2004.

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ABSTRACT Staphylococcus aureus SirA was previously identified as a lipoprotein, and SirB and SirC are thought to encode the transmembrane domains of an ABC transporter. Sir proteins show similarity to iron-siderophore transporters in several bacteria. Here, we show that the iron-regulated sirABC operon is divergently transcribed from the sbn operon that encodes enzymes involved in the synthesis of staphylobactin, a recently described siderophore produced by S. aureus. Mutation of either sirA or sirB increased the resistance of iron-starved S. aureus to streptonigrin and resulted in compromised growth in iron-restricted, but not iron-rich, media. We also demonstrated that sirA and sirB mutants are compromised in the ability to transport iron complexed to staphylobactin but are not compromised for uptake of other iron complexes, such as ferric hydroxamates, ferric enterobactin, or ferric citrate. SirA- and SirB-deficient S. aureus, however, retain the ability to produce staphylobactin. Moreover, we found that transcription from the sbn operon was increased, relative to the wild type, in both sirA and sirB knockout strains, likely in response to an increased level of iron starvation in these cells. These results provide evidence of a role for these proteins in iron import in S. aureus and for full fitness of the bacterium in iron-restricted environments and demonstrate a function for S. aureus genes encoding proteins involved in the transport of an endogenously produced siderophore.

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Morrissey, Julie A., Alan Cockayne, Philip J. Hill, and Paul Williams. "Molecular Cloning and Analysis of a Putative Siderophore ABC Transporter from Staphylococcus aureus." Infection and Immunity 68, no. 11 (2000): 6281–88. http://dx.doi.org/10.1128/.68.11.6281-6288.2000.

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29

Hiron, Aurelia, Brunella Posteraro, Marie Carrière, Laetitia Remy, Cécile Delporte, Marilena La Sorda, Maurizio Sanguinetti, Vincent Juillard, and Elise Borezée-Durant. "A nickel ABC-transporter of Staphylococcus aureus is involved in urinary tract infection." Molecular Microbiology 77, no. 5 (August 25, 2010): 1246–60. http://dx.doi.org/10.1111/j.1365-2958.2010.07287.x.

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30

Hiron, Aurelia, Brunella Posteraro, Marie Carrière, Laetitia Remy, Cécile Delporte, Marilena La Sorda, Maurizio Sanguinetti, Vincent Juillard, and Elise Borezée-Durant. "A nickel ABC-transporter of Staphylococcus aureus is involved in urinary tract infection." Molecular Microbiology 78, no. 3 (October 23, 2010): 788. http://dx.doi.org/10.1111/j.1365-2958.2010.07416.x.

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31

Peng, Qi, Lu Guo, Yu Dong, Tingrui Bao, Huiyuan Wang, Tao Xu, Ying Zhang, and Jian Han. "PurN Is Involved in Antibiotic Tolerance and Virulence in Staphylococcus aureus." Antibiotics 11, no. 12 (November 25, 2022): 1702. http://dx.doi.org/10.3390/antibiotics11121702.

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Staphylococcus aureus can cause chronic infections which are closely related to persister formation. Purine metabolism is involved in S. aureus persister formation, and purN, encoding phosphoribosylglycinamide formyltransferase, is an important gene in the purine metabolism process. In this study, we generated a ΔpurN mutant of the S. aureus Newman strain and assessed its roles in antibiotic tolerance and virulence. The ΔpurN in the late exponential phase had a significant defect in persistence to antibiotics. Complementation of the ΔpurN restored its tolerance to different antibiotics. PurN significantly affected virulence gene expression, hemolytic ability, and biofilm formation in S. aureus. Moreover, the LD50 (3.28 × 1010 CFU/mL) of the ΔpurN for BALB/c mice was significantly higher than that of the parental strain (2.81 × 109 CFU/mL). Transcriptome analysis revealed that 58 genes that were involved in purine metabolism, alanine, aspartate, glutamate metabolism, and 2-oxocarboxylic acid metabolism, etc., were downregulated, while 24 genes involved in ABC transporter and transferase activity were upregulated in ΔpurN vs. parental strain. Protein-protein interaction network showed that there was a close relationship between PurN and GltB, and SaeRS. The study demonstrated that PurN participates in the formation of the late exponential phase S. aureus persisters via GltB and regulates its virulence by activating the SaeRS two-component system.

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32

Hall, Jason A., and Ana M. Pajor. "Functional Reconstitution of SdcS, a Na+-Coupled Dicarboxylate Carrier Protein from Staphylococcus aureus." Journal of Bacteriology 189, no. 3 (November 17, 2006): 880–85. http://dx.doi.org/10.1128/jb.01452-06.

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ABSTRACT In Staphylococcus aureus, the transport of dicarboxylates is mediated in part by the Na+-linked carrier protein SdcS. This transporter is a member of the divalent-anion/Na+ symporter (DASS) family, a group that includes the mammalian Na+/dicarboxylate cotransporters NaDC1 and NaDC3. In earlier work, we cloned and expressed SdcS in Escherichia coli and found it to have transport properties similar to those of its eukaryotic counterparts (J. A. Hall and A. M. Pajor, J. Bacteriol. 187:5189-5194, 2005). Here, we report the partial purification and subsequent reconstitution of functional SdcS into liposomes. These proteoliposomes exhibited succinate counterflow activity, as well as Na+ electrochemical-gradient-driven transport. Examination of substrate specificity indicated that the minimal requirement necessary for transport was a four-carbon terminal dicarboxylate backbone and that productive substrate-transporter interaction was sensitive to substitutions at the substrate C-2 and C-3 positions. Further analysis established that SdcS facilitates an electroneutral symport reaction having a 2:1 cation/dicarboxylate ratio. This study represents the first characterization of a reconstituted Na+-coupled DASS family member, thus providing an effective method to evaluate functional, as well as structural, aspects of DASS transporters in a system free of the complexities and constraints associated with native membrane environments.

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33

Cockayne, Alan, Philip J. Hill, Nick B. L. Powell, Keith Bishop, Cate Sims, and Paul Williams. "Molecular Cloning of a 32-Kilodalton Lipoprotein Component of a Novel Iron-Regulated Staphylococcus epidermidis ABC Transporter." Infection and Immunity 66, no. 8 (August 1, 1998): 3767–74. http://dx.doi.org/10.1128/iai.66.8.3767-3774.1998.

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ABSTRACT Our previous studies identified two iron-regulated cytoplasmic membrane proteins of 32 and 36 kDa expressed by bothStaphylococcus epidermidis and Staphylococcus aureus. In this study we show by Triton X-114 phase partitioning and tritiated palmitic acid labelling that these proteins are lipoproteins which are anchored into the cytoplasmic membrane by their lipid-modified N termini. In common with those of some other gram-positive bacteria, these highly immunogenic lipoproteins were released from the bacterial cell into the culture supernatants, with release being promoted by growth of the bacteria under iron-restricted conditions. Immunoelectron microscopy with a monospecific rabbit antiserum to the 32-kDa S. epidermidis lipoprotein showed that the majority of the antigen was distributed throughout the staphylococcal cell wall. Only minor quantities were detected in the cytoplasmic membrane, and exposure of the lipoprotein on the bacterial surface was minimal. A monoclonal antibody raised to the 32-kDa lipoprotein of S. aureus was used in immunoblotting studies to investigate the conservation of this antigen among a variety of staphylococci. The monoclonal antibody reacted with polypeptides of 32 kDa in S. epidermidis and S. aureus and of 40 kDa in Staphylococcus hominis. No reactivity was detected with Staphylococcus lugdunensis,Staphylococcus cohni, or Staphylococcus haemolyticus. The gene encoding the 32-kDa lipoprotein fromS. epidermidis has been isolated from a Lambda Zap II genomic DNA library and found to be a component of an iron-regulated operon encoding a novel ABC-type transporter. The operon contains three genes, designated sitA, -B, and -C, encoding an ATPase, a cytoplasmic membrane protein, and the 32-kDa lipoprotein, respectively. SitC shows significant homology both with a number of bacterial adhesins, including FimA of Streptococcus parasanguis and ScaA of Streptococcus gordonii, and with lipoproteins of a recently described family of ABC transporters with proven or putative metal ion transport functions. Although the solute specificity of this novel transporter has not yet been determined, we speculate that it may be involved in either siderophore- or transferrin-mediated iron uptake in S. epidermidis.

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34

Lehman, McKenzie K., Natalie A. Sturd, Fareha Razvi, Dianne L. Wellems, Steven D. Carson, and Paul D. Fey. "Proline transporters ProT and PutP are required for Staphylococcus aureus infection." PLOS Pathogens 19, no. 1 (January 18, 2023): e1011098. http://dx.doi.org/10.1371/journal.ppat.1011098.

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Proline acquired via specific transporters can serve as a proteinogenic substrate, carbon and nitrogen source, or osmolyte. Previous reports have documented that Staphylococcus aureus, a major community and nosocomial pathogen, encodes at least four proline transporters, PutP, OpuC, OpuD, and ProP. A combination of genetic approaches and 3H-proline transport assays reveal that a previously unrecognized transporter, ProT, in addition to PutP, are the major proline transporters in S. aureus. Complementation experiments using constitutively expressed non-cognate promoters found that proline transport via OpuD, OpuC, and ProP is minimal. Both proline biosynthesis from arginine and proline transport via ProT are critical for growth when S. aureus is grown under conditions of high salinity. Further, proline transport mediated by ProT or PutP are required for growth in media with and without glucose, indicating both transporters function to acquire proline for proteinogenic purposes in addition to acquisition of proline as a carbon/nitrogen source. Lastly, inactivation of proT and putP resulted in a significant reduction (5 log10) of bacterial burden in murine skin-and-soft tissue infection and bacteremia models, suggesting that proline transport is required to establish a S. aureus infection.

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35

Pendas, Stefanos, Antonis Asiminas, Alexandros Katranidis, Costas Tsioptsias, Maria Pitou, Georgios Papadopoulos, and Theodora Choli-Papadopoulou. "SpAD Biofunctionalized Cellulose Acetate Scaffolds Inhibit Staphylococcus aureus Adherence in a Coordinating Function with the von Willebrand A1 Domain (vWF A1)." Journal of Functional Biomaterials 13, no. 1 (February 21, 2022): 21. http://dx.doi.org/10.3390/jfb13010021.

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Staphylococcus aureus is one of the major pathogens causing and spreading hospital acquired infections. Since it is highly resistant to new generation antibiotics, novel strategies have to be developed such as the construction of biofunctionalized non-adherent surfaces that will prevent its tethering and subsequent spread in the hospital environment. In this frame, the domain D of protein A (SpAD) of S. aureus has been immobilized onto cellulose acetate scaffolds by using the streptavidin/biotin interaction, in order to study its interaction with the A1 domain of von Willebrand factor (vWF A1), a protein essential for hemostasis, found in human plasma. Subsequently, the biofunctionalized cellulose acetate scaffolds were incubated with S. aureus in the presence and absence of vWF A1 at different time periods and their potential to inhibit S. aureus growth was studied with scanning electron microscopy (SEM). The SpAD biofunctionalized scaffolds perceptibly ameliorated the non-adherent properties of the material, and in particular, the interaction between SpAD and vWF A1 effectively inhibited the growth of S. aureus. Thus, the exhibition of significant non-adherent properties of scaffolds addresses their potential use for covering medical equipment, implants, and stents.

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36

Scully, Ingrid L., Yekaterina Timofeyeva, Arthur Illenberger, Peimin Lu, Paul A. Liberator, Kathrin U. Jansen, and Annaliesa S. Anderson. "Performance of a Four-Antigen Staphylococcus aureus Vaccine in Preclinical Models of Invasive S. aureus Disease." Microorganisms 9, no. 1 (January 15, 2021): 177. http://dx.doi.org/10.3390/microorganisms9010177.

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A Staphylococcus aureus four-antigen vaccine (SA4Ag) was designed for the prevention of invasive disease in surgical patients. The vaccine is composed of capsular polysaccharide type 5 and type 8 CRM197 conjugates, a clumping factor A mutant (Y338A-ClfA) and manganese transporter subunit C (MntC). S. aureus pathogenicity is characterized by an ability to rapidly adapt to the host environment during infection, which can progress from a local infection to sepsis and invasion of distant organs. To test the protective capacity of the SA4Ag vaccine against progressive disease stages of an invasive S. aureus infection, a deep tissue infection mouse model, a bacteremia mouse model, a pyelonephritis model, and a rat model of infectious endocarditis were utilized. SA4Ag vaccination significantly reduced the bacterial burden in deep tissue infection, in bacteremia, and in the pyelonephritis model. Complete prevention of infection was demonstrated in a clinically relevant endocarditis model. Unfortunately, these positive preclinical findings with SA4Ag did not prove the clinical utility of SA4Ag in the prevention of surgery-associated invasive S. aureus infection.

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37

Sharer, M. V., C. Su, N. V. Hegde, B. M. Jayarao, and L. M. Sordillo. "Differential Expression of the Lactose Transporter Gene Affects Growth of Staphylococcus aureus in Milk." Journal of Dairy Science 86, no. 7 (July 2003): 2373–81. http://dx.doi.org/10.3168/jds.s0022-0302(03)73831-4.

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38

Markham, P. N., and A. A. Neyfakh. "Inhibition of the multidrug transporter NorA prevents emergence of norfloxacin resistance in Staphylococcus aureus." Antimicrobial Agents and Chemotherapy 40, no. 11 (November 1996): 2673–74. http://dx.doi.org/10.1128/aac.40.11.2673.

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39

Nobre, Lígia S., and Lígia M. Saraiva. "Role of the Siderophore Transporter SirABC in the Staphylococcus aureus Resistance to Oxidative Stress." Current Microbiology 69, no. 2 (March 29, 2014): 164–68. http://dx.doi.org/10.1007/s00284-014-0567-y.

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40

Nakonieczna, Joanna, Monika Kossakowska-Zwierucho, Michalina Filipiak, Weronika Hewelt-Belka, Mariusz Grinholc, and Krzysztof Piotr Bielawski. "Photoinactivation of Staphylococcus aureus using protoporphyrin IX: the role of haem-regulated transporter HrtA." Applied Microbiology and Biotechnology 100, no. 3 (December 3, 2015): 1393–405. http://dx.doi.org/10.1007/s00253-015-7145-5.

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41

Adina-Zada, Abdussalam, Tonya N. Zeczycki, Martin St. Maurice, Sarawut Jitrapakdee, W. Wallace Cleland, and Paul V. Attwood. "Allosteric regulation of the biotin-dependent enzyme pyruvate carboxylase by acetyl-CoA." Biochemical Society Transactions 40, no. 3 (May 22, 2012): 567–72. http://dx.doi.org/10.1042/bst20120041.

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The activity of the biotin-dependent enzyme pyruvate carboxylase from many organisms is highly regulated by the allosteric activator acetyl-CoA. A number of X-ray crystallographic structures of the native pyruvate carboxylase tetramer are now available for the enzyme from Rhizobium etli and Staphylococcus aureus. Although all of these structures show that intersubunit catalysis occurs, in the case of the R. etli enzyme, only two of the four subunits have the allosteric activator bound to them and are optimally configured for catalysis of the overall reaction. However, it is apparent that acetyl-CoA binding does not induce the observed asymmetrical tetramer conformation and it is likely that, under normal reaction conditions, all of the subunits have acetyl-CoA bound to them. Thus the activation of the enzyme by acetyl-CoA involves more subtle structural effects, one of which may be to facilitate the correct positioning of Arg353 and biotin in the biotin carboxylase domain active site, thereby promoting biotin carboxylation and, at the same time, preventing abortive decarboxylation of carboxybiotin. It is also apparent from the crystal structures that there are allosteric interactions induced by acetyl-CoA binding in the pair of subunits not optimally configured for catalysis of the overall reaction.

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42

Wang, Yingyu, Xiaowei Li, Yang Wang, Stefan Schwarz, Jianzhong Shen, and Xi Xia. "Intracellular Accumulation of Linezolid and Florfenicol in OptrA-Producing Enterococcus faecalis and Staphylococcus aureus." Molecules 23, no. 12 (December 4, 2018): 3195. http://dx.doi.org/10.3390/molecules23123195.

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The optrA gene, which confers transferable resistance to oxazolidinones and phenicols, is defined as an ATP-binding cassette (ABC) transporter but lacks transmembrane domains. The resistance mechanism of optrA and whether it involves antibiotic efflux or ribosomal protection remain unclear. In this study, we determined the MIC values of all bacterial strains by broth microdilution, and used ultra-high performance liquid chromatography-tandem quadrupole mass spectrometry to quantitatively determine the intracellular concentrations of linezolid and florfenicol in Enterococcus faecalis and Staphylococcus aureus. Linezolid and florfenicol both accumulated in susceptible strains and optrA-carrying strains of E. faecalis and S. aureus. No significant differences were observed in the patterns of drug accumulation among E. faecalis JH2-2, E. faecalis JH2-2/pAM401, and E. faecalis JH2-2/pAM401+optrA, but also among S. aureus RN4220, S. aureus RN4220/pAM401, and S. aureus RN4220/pAM401+optrA. ANOVA scores also suggested similar accumulation conditions of the two target compounds in susceptible strains and optrA-carrying strains. Based on our findings, the mechanism of optrA-mediated resistance to oxazolidinones and phenicols obviously does not involve active efflux and the OptrA protein does not confer resistance via efflux like other ABC transporters.

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43

ADESIYUN, A. A., W. LENZ, and K. P. SCHAAL. "Phage Susceptibility and Enterotoxin Production by Staphylococcus aureus Strains Isolated from Nigerian Foods." Journal of Food Protection 55, no. 11 (November 1, 1992): 871–73. http://dx.doi.org/10.4315/0362-028x-55.11.871.

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The sensitivity of Staphylococcus aureus strains isolated from Nigerian foods to phages in the international phage sets for typing human and bovine strains of staphylococci was determined. The enterotoxigenicity of the strains was also determined using the avidin-biotin enzyme-linked immunosorbent assay and the reversed passive latex agglutination test (for staphylococcal enterotoxin D only). One hundred and five (67.7%) of 155 strains tested were susceptible to phages in both typing sets. Phages for staphylococci of human origin lysed all 105 typeable strains while those for staphylococci of bovine origin were responsible for the lysis of 92 strains. Phages in the different phage groups (mixed) were most frequently responsible for lysis, 29 (27.6%), followed by group III phages with 26 (24.8%) strains susceptible. Of the 155 strains tested, 122 (78.7%) were enterotoxigenic producing staphylococcal enterotoxins A, B, C, D, or a combination. Dried beef isolates were most enterotoxigenic (100.0%) and those from fermented milk least (68.8%). Staphylococcal enterotoxins C, B, and A were elaborated either singly or in combination by 71 (58.2%), 69 (56.6%), and 62 (50.8%) strains, respectively. It was concluded that a majority of staphylococcal strains isolated from Nigerian foods originated from humans and their high enterotoxigenicity could be a health risk to consumers.

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44

Truong-Bolduc, Q. C., P. M. Dunman, J. Strahilevitz, S. J. Projan, and D. C. Hooper. "MgrA Is a Multiple Regulator of Two New Efflux Pumps in Staphylococcus aureus." Journal of Bacteriology 187, no. 7 (April 1, 2005): 2395–405. http://dx.doi.org/10.1128/jb.187.7.2395-2405.2005.

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ABSTRACT In an analysis of the resistance mechanisms of an mgrA mutant, we identified two genes encoding previously undescribed transporters, NorB and Tet38. norB was 1,392 bp and encoded a predicted 49-kDa protein. When overexpressed, NorB led to an increase in resistance to hydrophilic quinolones, ethidium bromide, and cetrimide and also to sparfloxacin, moxifloxacin, and tetracycline, a resistance phenotype of the mgrA mutant. NorA and NorB shared 30% similarity, and NorB shared 30 and 41% similarities with the Bmr and Blt transporters of Bacillus subtilis, respectively. The second efflux pump was a more selective transporter that we have called Tet38, which had 46% similarity with the plasmid-encoded TetK efflux transporter of S. aureus. tet38 was 1,353 bp and encoded a predicted 49-kDa protein. Overexpression of tet38 produced resistance to tetracycline but not to minocycline and other drugs. norB and tet38 transcription was negatively regulated by MgrA. Limited binding of MgrA to the promoter regions of norB and tet38 was demonstrated by gel shift assays, suggesting that MgrA was an indirect regulator of norB and tet38 expression. The mgrA norB double mutant was reproducibly twofold more susceptible to the tested quinolones than the mgrA mutant. The mgrA tet38 double mutant became more susceptible to tetracycline than the wild-type parent strain. These data demonstrate that overexpression of NorB and Tet38 contribute, respectively, to the hydrophobic quinolone resistance and the tetracycline resistance of the mgrA mutant and that MgrA regulates expression of norB and tet38 in addition to its role in regulation of norA expression.

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45

Feng, Jiage, Ashleigh S. Paparella, William Tieu, David Heim, Sarah Clark, Andrew Hayes, Grant W. Booker, Steven W. Polyak, and Andrew D. Abell. "New Series of BPL Inhibitors To Probe the Ribose-Binding Pocket of Staphylococcus aureus Biotin Protein Ligase." ACS Medicinal Chemistry Letters 7, no. 12 (October 12, 2016): 1068–72. http://dx.doi.org/10.1021/acsmedchemlett.6b00248.

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46

Zheng, Xiaoliang, Yue Wang, Shengjun Bu, Zhibao Chen, and Jiayu Wan. "Point-of-care detection of 16S rRNA of Staphylococcus aureus based on multiple biotin-labeled DNA probes." Molecular and Cellular Probes 47 (October 2019): 101427. http://dx.doi.org/10.1016/j.mcp.2019.101427.

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47

Kögl, F., and W. J. van Wagtendonk. "Über die Bedeutung von Biotin für das Wachstum von Staphylococcus Pyogenes Aureus: 27. Mitteilung über pflanzliche Wachstumstoffe." Recueil des Travaux Chimiques des Pays-Bas 57, no. 7 (September 3, 2010): 747–54. http://dx.doi.org/10.1002/recl.19380570714.

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48

Schlag, Steffen, Stephan Fuchs, Christiane Nerz, Rosmarie Gaupp, Susanne Engelmann, Manuel Liebeke, Michael Lalk, Michael Hecker, and Friedrich Götz. "Characterization of the Oxygen-Responsive NreABC Regulon of Staphylococcus aureus." Journal of Bacteriology 190, no. 23 (September 26, 2008): 7847–58. http://dx.doi.org/10.1128/jb.00905-08.

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ABSTRACT Here, we investigate the functionality of the oxygen-responsive nitrogen regulation system NreABC in the human pathogen Staphylococcus aureus and evaluate its role in anaerobic gene regulation and virulence factor expression. Deletion of nreABC resulted in severe impairment of dissimilatory nitrate and nitrite reduction and led to a small-colony phenotype in the presence of nitrate during anaerobic growth. For characterization of the NreABC regulon, comparative DNA microarray and proteomic analyses between the wild type and nreABC mutant were performed under anoxic conditions in the absence and presence of nitrate. A reduced expression of virulence factors was not observed in the mutant. However, both the transcription of genes involved in nitrate and nitrite reduction and the accumulation of corresponding proteins were highly decreased in the nreABC mutant, which was unable to utilize nitrate as a respiratory oxidant and, hence, was forced to use fermentative pathways. These data were corroborated by the quantification of the extracellular metabolites lactate and acetate. Using an Escherichia coli-compatible two-plasmid system, the activation of the promoters of the nitrate and nitrite reductase operons and of the putative nitrate/nitrite transporter gene narK by NreBC was confirmed. Overall, our data indicate that NreABC is very likely a specific regulation system that is essential for the transcriptional activation of genes involved in dissimilatory reduction and transport of nitrate and nitrite. The study underscores the importance of NreABC as a fitness factor for S. aureus in anoxic environments.

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49

Stauff, Devin L., Danielle Bagaley, Victor J. Torres, Rose Joyce, Kelsi L. Anderson, Lisa Kuechenmeister, Paul M. Dunman, and Eric P. Skaar. "Staphylococcus aureus HrtA Is an ATPase Required for Protection against Heme Toxicity and Prevention of a Transcriptional Heme Stress Response." Journal of Bacteriology 190, no. 10 (March 7, 2008): 3588–96. http://dx.doi.org/10.1128/jb.01921-07.

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ABSTRACT During systemic infection, Staphylococcus aureus acquires nutrient iron from heme, the cofactor of vertebrate myoglobin and hemoglobin. Upon exposure to heme, S. aureus up-regulates the expression of the heme-regulated transporter, HrtAB. Strains lacking hrtAB exhibit increased sensitivity to heme toxicity, and upon heme exposure they elaborate a secreted protein response that interferes with the recruitment of neutrophils to the site of infection. Taken together, these results have led to the suggestion that hrtAB encodes an efflux system responsible for relieving the toxic effects of accumulated heme. Here we extend these observations by demonstrating that HrtA is the ATPase component of the HrtAB transport system. We show that HrtA is an Mn2+/Mg2+-dependent ATPase that functions at an optimal pH of 7.5 and exhibits in vitro temperature dependence uncommon to ABC transporter ATPases. Furthermore, we identify conserved residues within HrtA that are required for in vitro ATPase activity and are essential for the functionality of HrtA in vivo. Finally, we show that heme induces an alteration in the gene expression pattern of S. aureus ΔhrtA, implying the presence of a novel transcriptional regulatory mechanism responsible for the previously described immunomodulatory characteristics of hrtA mutants exposed to heme.

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50

Bamberger, David M., Betty L. Herndon, Jeffrey Fitch, Aaron Florkowski, and Vera Parkhurst. "Effects of Neutrophils on Cefazolin Activity and Penicillin-Binding Proteins in Staphylococcus aureus Abscesses." Antimicrobial Agents and Chemotherapy 46, no. 9 (September 2002): 2878–84. http://dx.doi.org/10.1128/aac.46.9.2878-2884.2002.

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ABSTRACT Bacteria survive within abscesses despite antimicrobial therapy, usually necessitating drainage. Our previous work showed that bacterial killing is diminished within the neutrophils of animals with abscesses. To further assess the role of neutrophils in Staphylococcus aureus survival and the poor activities of β-lactams in abscesses, tissue cage abscess-bearing rats were given polymorphonuclear leukocyte (PMN)-depleting antibody prior to and several times following inoculation of the tissue cages with S. aureus. Cefazolin (300 mg/kg of body weight/day) was administered to all animals in appropriately divided doses. After 7 days of antimicrobial therapy, the 17 animals that received anti-PMN serum had significantly fewer abscess neutrophils than the 18 controls and fewer abscess bacteria (5.55 versus 3.79 log10 CFU/ml [P = 0.04]) than the 18 controls. The data were consistent with the premise that cefazolin is more effective in abscesses depleted of neutrophils. To investigate further, S. aureus was incubated with rat peritoneal neutrophils; and bacterial cell membrane proteins were isolated, labeled with biotinylated ampicillin, separated by electrophoresis, blotted onto nitrocellulose, and stained for biotin reactivity. PBP 2 expression was consistently and significantly decreased after a brief, nonkilling PMN exposure. These experiments showed that PMN depletion enhanced the activity of cefazolin in the abscess milieu. Furthermore, altered bacterial cell wall cefazolin targets may be the mechanism by which the PMN diminishes antimicrobial activity, suggesting the importance of the staphylococcus-PMN interaction in the outcome of established infections.

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