Log in

Relevant bibliographies by topics / Beta-lactam antibiotics][Penicillin

Contents

Journal articles
Dissertations / Theses
Books
Book chapters

Academic literature on the topic 'Beta-lactam antibiotics][Penicillin'

Author: Grafiati

Published: 4 June 2021

Last updated: 3 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Beta-lactam antibiotics][Penicillin.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Beta-lactam antibiotics][Penicillin"

1

Terico, Adrienne T., and Jason C. Gallagher. "Beta-Lactam Hypersensitivity and Cross-Reactivity." Journal of Pharmacy Practice 27, no. 6 (August 14, 2014): 530–44. http://dx.doi.org/10.1177/0897190014546109.

Full text

Abstract:

Penicillin is the most frequently reported cause of drug allergy, and cross-reactivity of penicillins with other beta-lactam antibiotics is an area of debate. This review evaluates the available data on immunoglobulin E-mediated penicillin hypersensitivity and cross-reactivity with cephalosporin, carbapenem, and monobactam antibiotics. A MEDLINE search was conducted from 1950 to October 2013, and selected references from review articles were also evaluated. There is a wide variety in reported incidences of cross-reactivity between penicillins and cephalosporins or carbapenems, with early retrospective studies suggesting up to 41.7% and 47.4% cross-reactivity, respectively. Conversely, the use of monobactam antibiotics is frequently employed in the case of a penicillin allergy, as prescribers believe that there is no cross-reactivity between the 2 drug classes. More recent prospective studies suggest that the rates of cross-reactivity with cephalosporins and carbapenems are <5% and <1%, respectively. Similarities in penicillin and cephalosporin side chains may play a role in cross-reactivity between these classes. Cross-reactivity with monobactams is essentially negligible; however, there are some clinical data to support an interaction between ceftazidime and aztreonam, due to the similarity of their side chains. The data reviewed suggest that avoidance of other beta-lactams in patients with type 1 hypersensitivity to penicillins should be reconsidered.

APA, Harvard, Vancouver, ISO, and other styles

2

Bradley, Nicole, Yuman Lee, and Dana Weinstein. "Overview of Beta-Lactam Allergy and the Role of the Pharmacist in Management." Allergies 1, no. 2 (June 17, 2021): 128–36. http://dx.doi.org/10.3390/allergies1020011.

Full text

Abstract:

Unverified beta-lactam allergies are a substantial public health problem, as the majority of patients labeled as beta-lactam allergic do not have clinically significant allergies that may hinder the use beta-lactam therapy when indicated. Outdated or inaccurate beta-lactam or penicillin allergies can result in serious consequences, including suboptimal antibiotic therapy, increased risk of adverse effects, and use of broader spectrum antibiotics than indicated, which may contribute to antimicrobial resistance. The purpose of this review is to provide an overview of beta-lactam allergy and highlight the role of pharmacists in managing beta-lactam allergies. Studies have shown that pharmacists can play a vital role in allergy assessment, penicillin skin testing, beta-lactam desensitization, evaluation of beta-lactam cross-reactivity and recommending appropriate antibiotic therapy in patients with beta-lactam allergies.

APA, Harvard, Vancouver, ISO, and other styles

3

Asada, K., Y. Inaba, E. Tateda-Suzuki, K. Kuwahara-Arai, T. Ito, and K. Hiramatsu. "Evolution and resistance expression of MRSA. Evaluation of beta-lactam antibiotics against a set of isogenic strains with different types of phenotypic expression." Acta Biochimica Polonica 42, no. 4 (December 31, 1995): 517–24. http://dx.doi.org/10.18388/abp.1995_4905.

Full text

Abstract:

Methicillin-resistant Staphylococcus aureus (MRSA) has two mechanisms of resistance to beta-lactam antibiotics; one is mediated by mecA gene expression, and the other by penicillinase production. It has been generally accepted in the clinical field that beta-lactam antibiotics are not the drugs of choice for MRSA infection. In this report, however, ampicillin and penicillin G were shown to have relatively good activity against MRSA if combined with a beta-lactamase inhibitor, sulbactam. These beta-lactam antibiotics were found to have relatively high binding affinities to PBP2', the mecA-encoded MRSA-specific penicillin-binding protein. The possible therapeutic application of sulbactam/ampicillin against MRSA infection in combination with arbekacin, an aminoglycoside antibiotic newly developed and introduced into clinical use in Japan, is discussed.

APA, Harvard, Vancouver, ISO, and other styles

4

Wong, Tiffany, Adelle Atkinson, Geert t’Jong, Michael J. Rieder, Edmond S. Chan, and Elissa M. Abrams. "Beta-lactam allergy in the paediatric population." Paediatrics & Child Health 25, no. 1 (February 2020): 62. http://dx.doi.org/10.1093/pch/pxz179.

Full text

Abstract:

Abstract Beta-lactam allergy is commonly diagnosed in paediatric patients, but over 90% of individuals reporting this allergy are able to tolerate the medications prescribed after evaluation by an allergist. Beta-lactam allergy labels are associated with negative clinical and administrative outcomes, including use of less desirable alternative antibiotics, longer hospitalizations, increasing antibiotic-resistant infections, and greater medical costs. Also, children with true IgE-mediated allergy to penicillin medications are often advised to avoid all beta-lactam antibiotics, including cephalosporins, which is likely unnecessary in greater than 97% of those reporting penicillin allergies. Most patients can be safely treated with penicillin or amoxicillin if they do not have a history compatible with IgE-mediated or systemic, delayed reactions such as Stevens-Johnson syndrome (SJS), serum sickness-like reactions, drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome, or acute generalized exanthematous pustulosis (AGEP). Guidance is provided on how to stratify risk of beta-lactam allergy, and on test dosing and monitoring in the outpatient setting for patients deemed low risk. Guidance for patients at higher risk of beta-lactam allergy includes criteria for appropriate referral to allergists and the use of alternative antimicrobials, such as cephalosporins, while awaiting specialist assessment.

APA, Harvard, Vancouver, ISO, and other styles

5

Burroughs, Susan F., and Gerhard J. Johnson. "Beta-Lactam Antibiotics Inhibit Agonist-Stimulated Platelet Calcium Influx." Thrombosis and Haemostasis 69, no. 05 (1993): 503–8. http://dx.doi.org/10.1055/s-0038-1651641.

Full text

Abstract:

Summary(β-lactam antibiotics cause platelet dysfunction with reversible agonist-receptor inhibition, irreversible [14C]-penicillin binding, and inhibition of agonist-stimulated elevation in cytosolic Ca2+ ([Ca2+]i), occurring after 24 h exposure in vitro and after in vivo treatment. We investigated β-lactam antibiotic-induced inhibition of rises in [Ca2+]i stimulated by thrombin, sodium arachidonate or A23187 to determine whether Ca2+ influx or intracellular release was primarily affected. The mean rise in [Ca2+]i, measured with fura-2-AM, was inhibited 43.7-84.1% by penicillin when the extracellular Ca2+ concentration ([Ca2+]e) was 1 mM, but was significantly less inhibited when [Ca2+]e was <1 μM. NiCl2 (2 mM), that blocks Ca2+ influx, caused inhibition comparable to penicillin. MnCl2 (1 mM), that quenches the intracellular fura-2 signal, significantly decreased the rise in 1 mM [Ca2+]i when [Ca2+]e was 1 mM, but did not increase the inhibition caused by penicillin. Penicillin did not inhibit the rise in [Ca2+]i stimulated by inositol-1,4,5-trisphosphate or GTPγS. Therefore, β-lactam antibiotics inhibit agonist-induced elevations of [Ca2+]i primarily through inhibition of Ca2+ influx, which probably accounts for the irreversible inhibition of platelet function seen after prolonged in vitro or in vivo treatment.

APA, Harvard, Vancouver, ISO, and other styles

6

Lepage, S., M. Galleni, B. Lakaye, B. Joris, I. Thamm, and J. M. Frere. "Kinetic properties of the Bacillus licheniformis penicillin-binding proteins." Biochemical Journal 309, no. 1 (July 1, 1995): 49–53. http://dx.doi.org/10.1042/bj3090049.

Full text

Abstract:

In the analysis of the interactions between beta-lactam antibiotics and their target enzymes, it is often difficult to estimate the kinetic properties of the molecules which react rapidly with their targets and in consequence behave as the most efficient antibiotics. The combined utilization of fluorescein-labelled penicillins and of a new competition method has allowed an accurate determination of the high second-order rate constants characterizing the acylation of Bacillus licheniformis penicillin-binding protein 1 (PBP1) by penicillins and cephalosporins. Strategies were devised for measuring high acylation rates while avoiding titration effects. The method was also suitable for measuring the PBP kinetic parameters in intact cells. These results also confirmed that PBP1 is probably the main target of most beta-lactam antibiotics. Cephalexin, however, reacted faster with PBP3.

APA, Harvard, Vancouver, ISO, and other styles

7

Zaman, Rashed, Pranab Karmaker, SM Naimul Hasan, M. Hamidur Rahman, and Ariful Haque. "Drifted catalytic properties of β-lactamases due to unconstrained use of antibiotics." Journal of Bio-Science 19 (December 19, 2012): 37–42. http://dx.doi.org/10.3329/jbs.v19i0.12999.

Full text

Abstract:

Context: Antibiotic resistance is an old problem with new face as the rate of infections due to multidrug resistant bacteria is increasing everyday and the number of new antibiotics to overwhelm the problem is becoming smaller. Major mechanism beneath this growing resistance is concomitant with the changes in ?-lactamases catalytic activity and its functional enhancement. Objectives: In ?-lactamases secreting clinical isolates at least 10% are extended-spectrum ?-lactamases (ESBL) that are not even treatable with ?-lactamases inhibitor like clavulanic acids. This implies that the catalytic domains of ?-lactamases have been mutated towards higher pathogenicity. The aim of the present study is to define the changes in ?-lactamases catalytic efficiency against ?-lactam antibiotics and its inhibitors. Materials and Methods: In this research work we have used multiple drug resistant (MDR) strains from surgical site of infections. A rapid method was used for specific detection of bacterial ?-lactamases that uses ?-lactam antibiotics as substrates. In this, the end products (open beta-lactam ring forms) generated after separately incubating substrates with ?-lactamases producing strains. Those end products of antibiotics were highly fluorescent after specific treatment and could be analyzed visually under long-wave UV lamp for efficiency. Results: ?-lactamases secreting strains are variably capable of defending ?-lactam antibiotics. Interestingly, one of the E. coli strain secretes ESBL, this means that the strain is resistant against clavulanic acid. However, the most fascinating fact of the finding is that ideally the ?-lactamases supposed to hydrolyze Penicillin by default but in our isolates, ?-lactamases are not able to hydrolyze penicillin instead they hydrolyze amoxicillin, a derivative which replaced clinical use of penicillin. In addition to that we have identified the presence of New Delhi Metalo- beta- lactamase in one of the clinical isolates. Conclusion: Rate of evolution in microbes is very high. Thus we presume that some of the amino acids in the functional domain of ?-lactamases have been changed respective to extinct use of penicillin whereas it is effective against clinically used other beta lactam antibiotics. DOI: http://dx.doi.org/10.3329/jbs.v19i0.12999 J. bio-sci. 19 37-42, 2011

APA, Harvard, Vancouver, ISO, and other styles

8

Derakhshandeh, Maryam, and Majid Monajjemi. "Nano drug deliverer for ampicillin, clavulanic acid, imipenem, penicillin g and ticarcillin." Nexo Revista Científica 33, no. 01 (July 20, 2020): 121–36. http://dx.doi.org/10.5377/nexo.v33i01.10052.

Full text

Abstract:

Ampicillin belonging to the penicillin group of beta lactam antibiotics. Ampicillin is able to penetrate Gram positive and some Gram-negative bacteria. Imipenem (Primaxin) is an intravenous β-lactam antibiotic discovered by Merck scientists Burton Christensen, William Leanza, and Kenneth Wildonger in 1980 Ampicillin, Clavulanic acid, Imipenem, Penicillin G and Ticarcillin properties for the drug delivery with binding to SWCNNTs and SWBNNTs have been studied. Penicillin and its alteration Penicillin G or phenoxyacetic acid for Penicillin V is used for large scale production. Penicillin and other cell wall inhibitors are primarily specific against Gram positive bacteria because of higher percentage of peptidoglycan in the cell walls of these organisms. It was the first member of the carbapenem class of antibiotics. Based on our previous works we have modeled and simulated a drug delivery system of those antibiotics. The investigation of those antibiotics in binding with single-walled carbon nanotube (SWCNT) and SWBNNTs have been studied by theoretical methods. It has been established the best structural and functional of those antibiotics.

APA, Harvard, Vancouver, ISO, and other styles

9

Higazi, Abd Al-Roof, and Michael Mayer. "In Vitro Inhibition of Urokinase by Penicillins." Thrombosis and Haemostasis 60, no. 02 (1988): 305–7. http://dx.doi.org/10.1055/s-0038-1647049.

Full text

Abstract:

SummaryUrokinase activity was assayed by a two-stage globinolytic method and by a direct chromogenic assay. With both methods, the enzyme activity was found to be inhibited by penicillins. The inhibition by penicillin G, carbenicillin, cloxacillin and penicilloic acid was dose-dependent. The Kj of penicillin G and urokinase with the S-2444 as substrate is 4 mM. This compound exhibited a competitive pattern of inhibition. Ampicillin and 6-amino penicillanic acid failed to inhibit urokinase. These results imply that hydrophobic side chains of penicillins interact with the active site of urokinase. The present observation could be relevant in clinical situation in which high doses of beta-lactam antibiotics could modulate the endogenous fibrinolytic activity of circulating urokinase.

APA, Harvard, Vancouver, ISO, and other styles

10

Connelly, Sheila, Todd Parsley, Hui Ge, and Michael Kaleko. "Identification, Characterization, and Formulation of a Novel Carbapenemase Intended to Prevent Antibiotic-Mediated Gut Dysbiosis." Microorganisms 7, no. 1 (January 16, 2019): 22. http://dx.doi.org/10.3390/microorganisms7010022.

Full text

Abstract:

Antibiotics can damage the gut microbiome leading to opportunistic infections and the emergence of antibiotic resistance. Microbiome protection via antibiotic inactivation in the gastrointestinal (GI) tract represents a strategy to limit antibiotic exposure of the colonic microbiota. Proof of concept for this approach was achieved with an orally-administered beta-lactamase enzyme, SYN-004 (ribaxamase), that was demonstrated to degrade ceftriaxone excreted into the GI tract and protect the gut microbiome from antibiotic-mediated dysbiosis. Ribaxamase efficiently degrades penicillin and cephalosporin beta-lactam antibiotics, but is not active against carbapenems. To expand this microbiome protection strategy to include all classes of beta-lactams, three distinct carbapenemases were evaluated for manufacturability, antibiotic degradation spectrum, and stability in human intestinal fluid. E. coli production strains were generated for P2A, a novel metallo-enzyme isolated from B. cereus, New Delhi metallo-beta-lactamase (NDM), and Klebsiella pneumoniae carbapenemase (KPC). While all three enzymes effectively inactivated a broad range of antibiotics, including penicillins, most cephalosporins, and carbapenems in vitro, only P2A retained biological activity when incubated with human chyme. As functional stability in the intestinal tract is a key requirement for an orally-delivered enzyme, P2A was chosen as a potential clinical candidate. An enteric formulation of P2A was developed, called SYN-006, that was inert under high acid conditions, with enzyme dissolution occurring at pH > 5.5. SYN-006 has the potential to expand microbiome protection via antibiotic inactivation to include all classes of beta-lactam antibiotics.

APA, Harvard, Vancouver, ISO, and other styles

More sources

Dissertations / Theses on the topic "Beta-lactam antibiotics][Penicillin"

1

Rowe, Christine Janet. "Genetic engineering of penicillin biosynthesis." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307008.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

McGillivary, Angela. "Reactive solvent extraction of #beta#-lactam antibiotics and other anions." Thesis, London South Bank University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326763.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Crompton, I. A. "Studies on #beta#-lactamases." Thesis, University of Oxford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233406.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Ferreira, Juliana de Souza. "Processo intensificado de hidrolise enzimatica de penicilina G e purificação dos produtos em reator multi-estagio e contra-corrente." [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267674.

Full text

Abstract:

Orientadores: Telma Teixeira Franco, Adrianus Johannes Straanhof, Lucas Antonius Maria van der Wielen
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
Made available in DSpace on 2018-08-05T06:02:03Z (GMT). No. of bitstreams: 1 Ferreira_JulianadeSouza_D.pdf: 5552134 bytes, checksum: f2234304e4f228a88bb1b83073350bfa (MD5) Previous issue date: 2004
Resumo: Este trabalho estuda a hidrólise enzimática da penicilina G (PenG) em ácido 6-aminopenicilânico (6-APA) e ácido fenil acético (PAA). Em um reator contra-corrente multi-estágio e em baixos valores de pH, a reação enzimática ocorre na fase aquosa e os produtos são separados entre a fase aquosa e a fase orgânica (acetato de butila). Além disso, em pH baixo, a cristalização do 6-APA ocorre quando concentrações de PenG são altas. Ambos fenômenos deslocam o equilíbrio no sentido de conversão do substrato, promovendo alta produtividade. A primeira etapa deste trabalho refere-se à avaliação da atividade e estabilidade da penicilina amidase a baixo pH e na presença de acetato de butila (BuAc). A enzima apresentou máxima atividade na faixa de pH 8,0 - 9,0 e permaneceu estável mesmo em pHs baixos (3,0 - 6,0) num período de incubação de até 32 dias. Embora a atividade enzimática sofra um decréscimo de aproximadamente 80%, isto não representa empecilho para sua utilização no emprego da hidrólise de PenG em processo contínuo e bifásico (água e BuAc) em pH baixo. O efeito de PenG, PAA e BuAc na cristalização do 6-APA e os parâmetros cinéticos de cristalização também foram avaliados. Os resultados mostraram que as impurezas não exerceram efeito sobre a cristalização de 6-APA, na faixa de pH entre 4 e 5 e nas concentrações de impurezas de 0,55 mM - 3,0 mM. A avaliação da cinética de cristalização possibilitou o uso de um modelo que pode predizer as taxas de cristalização de 6-APA. Um modelo quantitativo foi desenvolvido para o cálculo do pH e das concentrações do substrato e dos produtos nos estágios do reator contra-corrente. Os dados fornecidos pelo modelo podem ser utilizados para otimizar as condições de operação como: estágio de alimentação, vazão volumétrica das fases e concentração inicial do substrato. Na última etapa deste trabalho foi feita uma revisão bibliográfica sobre biorreatores extrativos em que são apresentadas as vantagens de cada configuração e as restrições dos processos biocatalíticos. Através desta revisão, foi verificado que o uso de um sistema, formado por agitadores acoplados a hidrocic1ones em série, pode representar uma opção adequada de reatores multi-estágio contra-corrente para a hidrólise de PenG em escala de laboratório
Abstract: This work studies the enzymatic hydrolysis of penicillin G (PenG) into 6-aminopenicillanic acid (6-APA) and phenylacetic acid (PAA). In a multi-stage countercurrent reactor and at low pH, the enzymatic reaction takes place in the aqueous phase and the products are separated between the aqueous phase and organic phase (butyl acetate - BuAc). Furthermore, 6-APA crystallization occurs at low pH when PenG concentrations are high. Both phenomena shift the equilibrium towards conversion of substrate, favoring high productivity. The first step of this work, concerns the evaluation of activity and stability of penicillin amidase at low pH and in the presence of butyl acetate (BuAc). The enzyme presented the maximum activity in the pH 8.0 - 9.0 and remained stable at low pHs (3.06.0) during at least 32 days. Although the enzyme activity decreased by 80%, this does not represent a drawback in the application of a biphasic (water and BuAc) and continuous PenG hydrolysis at low pH. The effect of PenG, PAA and BuAc in APA crystallization and the kinetic parameters were also analyzed. The results showed that impurities have no effect on APA crystallization, in the pH range 4 - 5 and in the impurity concentrations of 0.55 mM - 3.0 mM. The evaluation of crystallization kinetics allowed the use of a mo del that predicts the APA crystallization rates. A quantitative model was developed in order to calculate the pH and substrates and products concentrations in the countercurrent reactor. The data provided by the model can be used to optimize the operation conditions: stage of feed, flow rate of phases and initial substrate concentration. In the last step of this work, a literature review concerning extractive bioreactor was made. This review presents the advantages of each configuration and the restrictions of the biocatalytic processes. Through this review, a integrated system of mixers and hydrocydone was suggested as an appropriate option of multi-stage countercurrent reactor for PenG hydrolysis in laboratory scale
Doutorado
Desenvolvimento de Processos Químicos
Doutor em Engenharia Química

APA, Harvard, Vancouver, ISO, and other styles

5

Deaguero, Andria Lynn. "Improving the enzymatic synthesis of semi-synthetic beta-lactam antibiotics via reaction engineering and data-driven protein engineering." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42727.

Full text

Abstract:

Semi-synthetic β-lactam antibiotics are the most prescribed class of antibiotics in the world. Chemical coupling of a β-lactam moiety with an acyl side chain has dominated the industrial production of semi-synthetic β-lactam antibiotics since their discovery in the early 1960s. Enzymatic coupling of a β-lactam moiety with an acyl side chain can be accomplished in a process that is much more environmentally benign but also results in a much lower yield. The goal of the research presented in this dissertation is to improve the enzymatic synthesis of β-lactam antibiotics via reaction engineering, medium engineering and data-drive protein engineering. Reaction engineering was employed to demonstrate that the hydrolysis of penicillin G to produce the β-lactam nucleus 6-aminopenicillanic acid (6-APA), and the synthesis of ampicillin from 6-APA and (R)-phenylglycine methyl ester ((R)-PGME), can be combined in a cascade conversion. In this work, penicillin G acylase (PGA) was utilized to catalyze the hydrolysis step, and PGA and α-amino ester hydrolase (AEH) were both studied to catalyze the synthesis step. Two different reaction configurations and various relative enzyme loadings were studied. Both configurations present a promising alternative to the current two-pot set-up which requires intermittent isolation of the intermediate, 6-APA. Medium engineering is primarily of interest in β-lactam antibiotic synthesis as a means to suppress the undesired primary and secondary hydrolysis reactions. The synthesis of ampicillin from 6-APA and (R)-PGME in the presence of ethylene glycol was chosen for study after a review of the literature. It was discovered that the transesterification product of (R)-PGME and ethylene glycol, (R)-phenylglycine hydroxyethyl ester, is transiently formed during the synthesis reactions. This never reported side reaction has the ability to positively affect yield by re-directing a portion of the consumption of (R)-PGME to an intermediate that could be used to synthesize ampicillin, rather than to an unusable hydrolysis product. Protein engineering was utilized to alter the selectivity of wild-type PGA with respect to the substituent on the alpha carbon of its substrates. Four residues were identified that had altered selectivity toward the desired product, (R)-ampicillin. Furthermore, the (R)-selective variants improved the yield from pure (R)-PGME up to 2-fold and significantly decreased the amount of secondary hydrolysis present in the reactions. Overall, we have expanded the applicability of PGA and AEH for the synthesis of semi-synthetic β-lactam antibiotics. We have shown the two enzymes can be combined in a novel one-pot cascade, which has the potential to eliminate an isolation step in the current manufacturing process. Furthermore, we have shown that the previously reported ex-situ mixed donor synthesis of ampicillin for PGA can also occur in-situ in the presence of a suitable side chain acyl donor and co-solvent. Finally, we have made significant progress towards obtaining a selective PGA that is capable of synthesizing diastereomerically pure semi-synthetic β-lactam antibiotics from racemic substrates.

APA, Harvard, Vancouver, ISO, and other styles

6

Yao, Zhizhong. "Using Live Cell Imaging to Probe Biogenesis of the Gram-Negative Cell Envelope." Thesis, Harvard University, 2012. http://dissertations.umi.com/gsas.harvard:10230.

Full text

Abstract:

In Gram-negative bacteria, the three-layered cell envelope, including the cell wall, outer and inner membranes, is essential for cell survival in the changing, and often hostile environments. Conserved in all prokaryotes, the cell wall is incredibly thin, yet it functions to prevent osmotic lysis in diluted conditions. Based on observations obtained by genetic and chemical perturbations, time-lapse live cell imaging, quantitative imaging and statistical analysis, Part I of this dissertation explores the molecular and physical events leading to cell lysis induced by division-specific beta-lactams. We found that such lysis requires the complete assembly of all essential components of the cell division apparatus and the subsequent recruitment of hydrolytic amidases. We propose that division-specific beta-lactams lyze cells by inhibiting FtsI (PBP3) without perturbing the normal assembly of the cell division machinery and the consequent activation of cell wall hydrolases. On the other hand, we demonstrated that cell lysis by beta-lactams proceeds through four physical phases: elongation, bulge formation, bulge stagnation and lysis. Bulge formation dynamics is determined by the specific perturbation of the cell wall and outer membrane plays an independent role in stabilizing the bulge once it is formed. The stabilized bulge delays lysis, and allows escape and recovery upon drug removal. Asymmetrical in structure and unique to Gram-negative bacteria, outer membrane prevents the passage of many hydrophobic, toxic compounds. Together with inner membrane and the cell wall, three layers of the Gram-negative cell envelope must be well coordinated throughout the cell cycle to allow elongation and division. Part II of this dissertation explores the essentiality of the LPS layer, the outer leaflet of the outer membrane. Using a conditional mutant severely defective in LPS transport, we found that mutations in the initiation phase of fatty acid synthesis suppress cells defective in LPS transport. The suppressor cells are remarkably small with a 70% reduction in cell volume and a 50 % reduction in growth rate. They are also blind to nutrient excess with respect to cell size control. We propose a model where fatty acid synthesis regulates cell size in response to nutrient availability, thereby influencing growth rate.
Chemistry and Chemical Biology

APA, Harvard, Vancouver, ISO, and other styles

7

Cacciatore, Giuseppe. "Screening auf Rückstände von [beta]-Lactam-Antibiotika [Beta-Lactam-Antibiotika] in Milch: Entwicklung eines optischen Biosensor-Assays mit Penicillin-bindenden Proteinen." [S.l. : s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=974861820.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Templey, Margaret Patricia. "The synthesis of some new heterocyclic analogues of the beta-lactam antibiotics." Thesis, University of Bath, 1988. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384557.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Orford, Colin David. "The enzymes and intermediates involved in the early stages of #beta#-lactam antibiotic biosynthesis in Penicillium chrysogenum." Thesis, University of Westminster, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252655.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Wolfers, Simon [Verfasser], Ulrich [Akademischer Betreuer] Kück, and Nicole [Akademischer Betreuer] Frankenberg. "Bioinformatische und funktionelle Analysen bei dem \(\beta\)-Lactam-Antibiotika-Produzenten \(\it Penicillium\) \(\it chrysogenum\) / Simon Wolfers. Gutachter: Ulrich Kück ; Nicole Frankenberg." Bochum : Ruhr-Universität Bochum, 2015. http://d-nb.info/1079843973/34.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Books on the topic "Beta-lactam antibiotics][Penicillin"

1

H, Bentley P., Southgate R, and Royal Society of Chemistry (Great Britain). Fine Chemicals and Medicinals Group., eds. Recent advances in the chemistry of [beta]-lactam antibiotics: The proceedings of the fourth international symposium. London: Royal Society of Chemistry, 1989.

Find full text

APA, Harvard, Vancouver, ISO, and other styles

2

(Editor), R. Southgate, ed. Recent Advances in the Chemistry of B-Lactam Antibiotics (Special Publication, No 70). Science and Behavior Books, 1989.

Find full text

APA, Harvard, Vancouver, ISO, and other styles

3

H, Bentley P., and Southgate R, eds. Recent advances in the chemistry of. Royal Society of Chemistry, 1989.

Find full text

APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Beta-lactam antibiotics][Penicillin"

1

Brakhage, Axel A., Petra Spröte, Qusai Al-Abdallah, Alexander Gehrke, Hans Plattner, and André Tüncher. "Regulation of Penicillin Biosynthesis in Filamentous Fungi." In Molecular Biotechnolgy of Fungal beta-Lactam Antibiotics and Related Peptide Synthetases, 45–90. Berlin, Heidelberg: Springer Berlin Heidelberg, 2004. http://dx.doi.org/10.1007/b99257.

Full text

APA, Harvard, Vancouver, ISO, and other styles

2

Jacob, George, and Martina N. Cummins. "Common Organisms Responsible for Healthcare-associated Infection (HCAI)." In Tutorial Topics in Infection for the Combined Infection Training Programme. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198801740.003.0026.

Full text

Abstract:

MRSA are S. aureus which become methicillin resistant by the acquisition of the mec A gene which is on a mobile chromosomal determinant called staphylococcal cassette chromosome mec (SCC mec). The mec A gene encodes for a penicillin- binding protein (PBP2a) which has a low affinity for isoxazolyl-penicillins (MICs to oxacillin/ meticillin ≥ 4μg/ ml) and is resistant to all classes of beta-lactam antibiotics. Current Department of Health (DOH) guidance (2014) recommends that mandatory MRSA screening be streamlined to include only: ● All patient admissions to high- risk units; ● Healthcare workers; and ● All patients previously identified as colonized or infected with MRSA. The guidance also advises Trusts to follow local risk assessment policies to identify other potential high- risk units or units with a history of high endemicity of MRSA; and The guidance also recommends regular auditing of compliance with MRSA screening policy. The 2006 guideline for the control and prevention of MRSA in healthcare facilities recommends the following four measures. ● Isolation MRSA- positive patients should be nursed in a single room or if none is available, cohorting into a bay after risk assessment. Patient movement, and the number of staff and visitors looking after the patient, should be minimized. ● Hand hygiene and use of personal protective equipment (PPE) All staff and visitors should decontaminate their hands with soap and water/or an alcohol rub before and after contact with the patient or their immediate surroundings. Single-use disposable gloves and aprons/non- permeable gowns should be used by staff and visitors if there is a risk of contamination with body fluids. ● Disposal of waste and laundry All waste from colonized/ infected patients should be placed in the infectious waste stream. All linen and bedding from patients colonized/infected with MRSA should be considered as contaminated and processed as infected linen. ● Cleaning and decontamination The patient’s room should be cleaned/disinfected daily with an appropriate detergent/disinfectant as per local policy. On discharge of the patient, the room needs to be terminally cleaned before it is reused. All patient equipment should either be single-patient use or be cleaned, disinfected, and sterilized.

APA, Harvard, Vancouver, ISO, and other styles

3

Midtvedt, Tore. "Penicillins, cephalosporins, other beta-lactam antibiotics, and tetracyclines." In Side Effects of Drugs Annual, 491–508. Elsevier, 2011. http://dx.doi.org/10.1016/b978-0-444-53741-6.00025-8.

Full text

APA, Harvard, Vancouver, ISO, and other styles

4

Toussaint, Kimberly A., and Jason C. Gallagher. "Penicillins, Cephalosporins, Other Beta-Lactam Antibiotics and Tetracyclines." In Side Effects of Drugs Annual, 347–61. Elsevier, 2014. http://dx.doi.org/10.1016/b978-0-444-63407-8.00025-3.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Midtvedt, T. "Penicillins, cephalosporins, other beta-lactam antibiotics, and tetracyclines." In Side Effects of Drugs Annual, 262–70. Elsevier, 2003. http://dx.doi.org/10.1016/s0378-6080(03)80032-6.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Midtvedt, Tore. "Penicillins, cephalosporins, other beta-lactam antibiotics, and tetracyclines." In Side Effects of Drugs Annual, 242–50. Elsevier, 2004. http://dx.doi.org/10.1016/s0378-6080(04)80032-1.

Full text

APA, Harvard, Vancouver, ISO, and other styles

7

Midtvedt, Tore. "Penicillins, cephalosporins, other beta-lactam antibiotics, and tetracyclines." In Side Effects of Drugs Annual 28, 265–73. Elsevier, 2005. http://dx.doi.org/10.1016/s0378-6080(05)80447-7.

Full text

APA, Harvard, Vancouver, ISO, and other styles

8

Midtvedt, Tore. "Penicillins, cephalosporins, other beta-lactam antibiotics, and tetracyclines." In Side Effects of Drugs Annual, 280–96. Elsevier, 2008. http://dx.doi.org/10.1016/s0378-6080(08)00025-1.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Midtvedt, Tore. "Penicillins, cephalosporins, other beta-lactam antibiotics, and tetracyclines." In Side Effects of Drugs Annual, 413–25. Elsevier, 2009. http://dx.doi.org/10.1016/s0378-6080(09)03125-0.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Midtvedt, Tore. "Penicillins, cephalosporins, other beta-lactam antibiotics, and tetracyclines." In Side Effects of Drugs Annual, 445–60. Elsevier, 2010. http://dx.doi.org/10.1016/s0378-6080(10)32025-3.

Full text

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!