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Academic literature on the topic 'Triosephosphate isomerases'

Author: Grafiati

Published: 4 June 2021

Last updated: 2 February 2022

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Journal articles on the topic "Triosephosphate isomerases"

1

Walden, H., G. Taylor, H. Lilie, T. Knura, and R. Hensel. "Triosephosphate isomerase of the hyperthermophile Thermoproteus tenax: thermostability is not everything." Biochemical Society Transactions 32, no. 2 (April 1, 2004): 305. http://dx.doi.org/10.1042/bst0320305.

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The triosephosphate isomerase of the hyperthermophilic crenarchaeum Thermoproteus tenax (TtxTIM) represents a homomeric tetramer. Unlike the triosephosphate isomerases of other hyperthermophiles, however, the association of the TtxTIM tetramers is looser, allowing a reversible dissociation into inactive dimers. The dimer/tetramer equilibrium of TtxTIM is shifted to the tetrameric state through a specific interaction with glycerol-1-phosphate dehydrogenase of T. tenax, suggesting that higher oligomerization of the TtxTIM serves functional rather than stabilizing purposes.

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Áabrahám, Magdolna, A. Alexin, and B. Szajáni. "Immobilized triosephosphate isomerases a comparative study." Applied Biochemistry and Biotechnology 36, no. 1 (July 1992): 1–12. http://dx.doi.org/10.1007/bf02950771.

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3

Zhang, Y., K. U. Yuksel, and R. W. Gracy. "Terminal Marking of Avian Triosephosphate Isomerases by Deamidation and Oxidation." Archives of Biochemistry and Biophysics 317, no. 1 (February 1995): 112–20. http://dx.doi.org/10.1006/abbi.1995.1142.

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4

Del Buono, Daniele, Bhakti Prinsi, Luca Espen, and Luciano Scarponi. "Triosephosphate Isomerases in Italian Ryegrass (Lolium multiflorum): Characterization and Susceptibility to Herbicides." Journal of Agricultural and Food Chemistry 57, no. 17 (September 9, 2009): 7924–30. http://dx.doi.org/10.1021/jf901681q.

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FIGUEROA-ANGULO, ELISA E., PRISCILA ESTRELLA-HERNÁNDEZ, HOLJES SALGADO-LUGO, ADRIÁN OCHOA-LEYVA, ARMANDO GÓMEZ PUYOU, SILVIA S. CAMPOS, GABRIELA MONTERO-MORAN, et al. "Cellular and biochemical characterization of two closely related triosephosphate isomerases from Trichomonas vaginalis." Parasitology 139, no. 13 (August 29, 2012): 1729–38. http://dx.doi.org/10.1017/s003118201200114x.

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SUMMARYThe glycolytic enzyme triosephosphate isomerase catalyses the isomerization between glyceraldehyde 3-phosphate and dihydroxyacetone phosphate. Here we report that Trichomonas vaginalis contains 2 fully functional tpi genes. Both genes are located in separated chromosomal context with different promoter regulatory elements and encode ORFs of 254 amino acids; the only differences between them are the character of 4 amino acids located in α-helices 1, 2 and 8. Semi-quantitative RT-PCR assays showed that tpi2 transcript is approximately 3·3-fold more abundant than tpi1. Using an anti-TvTIM2 polyclonal antibody it was demonstrated that TIM proteins have a cytoplasmic localization and both enzymes are able to complement an Escherichia coli strain carrying a deletion of its endogenous tpi gene. Both TIM proteins assemble as dimers and their secondary structure assessment is essentially identical to TIM from Saccharomyces cerevisiae. The kinetic catalytic constants of the recombinant enzymes using glyceraldehyde-3-phosphate as substrate are similar to the catalytic constants of TIMs from other organisms including parasitic protozoa. As T. vaginalis depends on glycolysis for ATP production, we speculate 2 possible reasons to maintain a duplicated tpi copy on its genome: an increase in gene dosage or an early event of neofunctionalization of TIM as a moonlighting protein.

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Aguirre, Yolanda, Nallely Cabrera, Beatriz Aguirre, Ruy Pérez-Montfort, Alejandra Hernandez-Santoyo, Horacio Reyes-Vivas, Sergio Enríquez-Flores, et al. "Different contribution of conserved amino acids to the global properties of triosephosphate isomerases." Proteins: Structure, Function, and Bioinformatics 82, no. 2 (October 18, 2013): 323–35. http://dx.doi.org/10.1002/prot.24398.

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7

Blacklow, Stephen C., and Jeremy R. Knowles. "How can a catalytic lesion be offset? The energetics of two pseudorevertant triosephosphate isomerases." Biochemistry 29, no. 17 (May 1990): 4099–108. http://dx.doi.org/10.1021/bi00469a012.

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8

Wierenga, R. K., T. V. Borcher, and M. E. M. Noble. "Crystallographic binding studies with triosephosphate isomerases: Conformational changes induced by substrate and substrate-analogues." FEBS Letters 307, no. 1 (July 27, 1992): 34–39. http://dx.doi.org/10.1016/0014-5793(92)80897-p.

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9

Rodríguez-Bolaños, Monica, Nallely Cabrera, and Ruy Perez-Montfort. "Identification of the critical residues responsible for differential reactivation of the triosephosphate isomerases of two trypanosomes." Open Biology 6, no. 10 (October 2016): 160161. http://dx.doi.org/10.1098/rsob.160161.

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The reactivation of triosephosphate isomerase (TIM) from unfolded monomers induced by guanidine hydrochloride involves different amino acids of its sequence in different stages of protein refolding. We describe a systematic mutagenesis method to find critical residues for certain physico-chemical properties of a protein. The two similar TIMs of Trypanosoma brucei and Trypanosoma cruzi have different reactivation velocities and efficiencies. We used a small number of chimeric enzymes, additive mutants and planned site-directed mutants to produce an enzyme from T. brucei with 13 mutations in its sequence, which reactivates fast and efficiently like wild-type (WT) TIM from T. cruzi , and another enzyme from T. cruzi, with 13 slightly altered mutations, which reactivated slowly and inefficiently like the WT TIM of T. brucei . Our method is a shorter alternative to random mutagenesis, saturation mutagenesis or directed evolution to find multiple amino acids critical for certain properties of proteins.

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10

GAO, Xiu-Gong, Georgina GARZA-RAMOS, Emma SAAVEDRA-LIRA, Nallely CABRERA, Marietta T. de GÓMEZ-PUYOU, Ruy PEREZ-MONTFORT, and Armando GÓMEZ-PUYOU. "Reactivation of triosephosphate isomerase from three trypanosomatids and human: effect of Suramin." Biochemical Journal 332, no. 1 (May 15, 1998): 91–96. http://dx.doi.org/10.1042/bj3320091.

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The reactivation of the homodimeric triosephosphate isomerases (TIMs) from Trypanosoma brucei, T. cruzi, Leishmania mexicana and humans was determined after their denaturation with guanidine hydrochloride. In the range of 2–32 µg of T. brucei TIM per ml and 0.2–5 µg of the other enzymes per ml, the rate and extent of TIM reactivation depended on protein concentration, indicating that at these protein concentrations, the rate-limiting step of reactivation is monomer association and not monomer folding. The rate of monomer association was more than one order of magnitude lower in the T. brucei enzyme than in the other three enzymes. Suramin is a drug of choice in the treatment of sleeping sickness, but its mechanism of action is not known. At micromolar concentrations, Suramin inhibited the reactivation of the four enzymes, but the extent of inhibition by Suramin decreased with increasing protein concentration as consequence of a diminution of the life time of the folded monomer. Since the life time of the monomer of T. brucei TIM is longer than that of the other enzymes, Suramin is a more effective inhibitor of the reactivation of TIM from T. brucei, particularly at monomer concentrations above 1 µg of protein per ml (monomer concentration approx. 37 nM). Compounds that are structurally related to Suramin also inhibit TIM reactivation; their effect was about five times more pronounced in the enzyme from T. brucei than in human TIM.

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Dissertations / Theses on the topic "Triosephosphate isomerases"

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Yüksel, K. Umit. "Molecular Aging of Triosephosphate Isomerase." Thesis, North Texas State University, 1987. https://digital.library.unt.edu/ark:/67531/metadc935641/.

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Alahuhta, M. (Markus). "Protein crystallography of triosephosphate isomerases: functional and protein engineering studies." Doctoral thesis, University of Oulu, 2008. http://urn.fi/urn:isbn:9789514287909.

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Abstract The aim of this PhD-study was to better understand the structure-function relationship of triosephosphate isomerase (TIM) and to use this expertise to change its substrate specificity. TIM is an important enzyme of the glycolytic pathway which catalyzes the interconversion of D-glyceraldehyde phosphate (D-GAP) and dihydroxyacetone phosphate (DHAP). Two main subjects are discussed: the engineering of monomeric TIM to create new substrate specificity and the structure-function relationship studies of the catalytically important mobile loop6. The starting point for the protein engineering project was the monomeric ml8bTIM, with an extended binding pocket between loop7 and loop8. Rational protein engineering efforts have resulted in a new variant called A-TIM that can competently bind wild type transition state analogues. A-TIM was also able to bind citrate, a compound that the wild type TIM does not bind. This A-TIM citrate complex structure is a good starting point for future protein engineering efforts. Based on the assumption that it would be beneficial for the monomeric forms of TIM to have loop6 closed permanently to increase the population of competent active sites, two point mutation variants, A178L and P168A were generated and characterized. The A178L-mutation was made to favor the closed conformation of loop6 through steric clashes in the open conformation. The P168A variant was made to stabilize the closed conformation of loop6 by removing strain. The A178L mutation induced some features of the closed conformation, but did not result in a closed conformation in the absence of ligands. Our structural studies also show that the P168A mutation does not favor the closed conformation either. However, the structures of the unliganded and liganded P168A variant, together with other known TIM structures show that the substrate binding first induces closure of loop7. This conformational switch subsequently forces loop6 to adopt its closed conformation. The protein engineering project was successful, but the efforts to find variants with a permanently closed loop6 did not fully succeed. In the context of this thesis a monomeric variant of TIM, with new binding properties, was created. Nevertheless, A-TIM still competently binds the inhibitors and transition state analogues of wild type TIM. Also, when combined, results discussed in the context of this thesis indicate that in wild type TIM the closure of loop7 after ligand binding is the initial step in the series of conformational changes that lead to the formation of the competent active site
Tiivistelmä Tämän väitöskirjatyön tarkoituksena oli oppia paremmin ymmärtämään trioosifosfaatti-isomeraasin (TIM) toimintamekanismeja sen rakenteen perusteella ja käyttää tätä tietämystä samaisen proteiinin muokkaamiseen uusiin tarkoituksiin. TIM on keskeinen entsyymi solun energian tuotannossa ja sen toiminta on välttämätöntä kaikille eliöille. Tämän vuoksi on tärkeää oppia ymmärtämään miten se saavuttaa tehokkaan reaktionopeutensa ja miksi se katalysoi vain D-glyseraldehydi-3-fosfaattia (D-GAP) ja dihydroksiasetonifosfaattia (DHAP). TIM:n toiminta mekanismien ymmärtämiseksi sen aminohapposekvenssiä muokattiin kahdesta kohtaa (P168A ja A178L) ja seuraukset todettiin mittaamalla tuotettujen proteiinien stabiilisuutta optisesti eri lämpötiloissa ja selvittämällä niiden kolmiulotteinen rakenne käyttäen röntgensädekristallografiaa. Mutaatioita tehtiin dimeeriseen villityypin TIM:in (wtTIM) ja jo aikaisemmin muokattuun monomeeriseen TIM:in (ml1TIM). Näiden mutaatioiden tarkoituksena oli suosia entsyymin aktiivista konformaatiota, jossa reaktion kannalta välttämätön vapaasti liikkuva peptidisilmukka numero 6 on suljetussa konformaatiossa. Monomeerisissä TIM:ssa peptidisilmukka numero 6:n ei ole välttämätöntä aueta. Tulokset mutaatiokokeista olivat osittain lupaavia. P168A-mutaatio lisäsi D-GAP:in sitoutumista, mutta rikkoi tärkeän mekanismin suljetussa, ligandia sitovassa, konformaatiossa. A178L-mutaatio aiheutti muutoksia avoimeen konformaatioon ja teki siitä suljettua konformaatiota muistuttavan jopa ilman ligandia, mutta samalla koko proteiini muuttui epävakaammaksi. Näistä kahdesta mutaatiosta A178L voisi olla hyödyllinen muokattujen TIM-versioiden ominaisuuksien parantamiseksi. Lisäksi yhdessä jo aikaisemmin julkaistujen yksityiskohtien kanssa nämä tulokset tekevät mahdolliseksi esittää tarkennusta siihen miten TIM toimii kun ligandi saapuu sen lähettyville. Tämän väitöskirjatyön yksi tavoite oli myös muokata edelleen monomeeristä TIM versiota (ml8bTIM), joka on suunniteltu siten, että se voi mahdollisesti sitoa uudenlaisia ligandeja. Tämä projekti vaati onnistuakseen 20 eri versiota ml8bTIM:n sekvenssistä ja noin 30 rakennetta. Uusia ligandeja sitova muoto (A-TIM) sitoi onnistuneesti sitraattia ja villityypin TIM:n inhibiittoreita. Erityisen lupaavaa oli, että A-TIM sitoi myös bromohydroksiasetonifosfaattia (BHAP), joka sitoutuu ainoastaan toimivaan aktiiviseen kohtaan. Nämä tulokset osoittavat, että A-TIM kykenee tarvittaessa katalysoimaan isomerisaatio reaktion uudenlaisille molekyyleille. Esimerkiksi katalysoimaan isomerisointireaktiota sokerianalogien tuotannossa

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3

Craig, Leonard C. (Leonard Callaway). "Analysis of a Human Transfer RNA Gene Cluster and Characterization of the Transcription Unit and Two Processed Pseudogenes of Chimpanzee Triosephosphate Isomerase." Thesis, University of North Texas, 1990. https://digital.library.unt.edu/ark:/67531/metadc331579/.

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An 18.5-kb human DNA segment was selected from a human XCharon-4A library by hybridization to mammalian valine tRNAiAc and found to encompass a cluster of three tRNA genes. Two valine tRNA genes with anticodons of AAC and CAC, encoding the major and minor cytoplasmic valine tRNA isoacceptors, respectively, and a lysine tRNAcuu gene were identified by Southern blot hybridization and DNA sequence analysis of a 7.1-kb region of the human DNA insert. At least nine Alu family members were found interspersed throughout the human DNA fragment. The tRNA genes are accurately transcribed by RNA polymerase III in a HeLa cell extract, since the RNase Ti fingerprints of the mature-sized tRNA transcription products are consistent with the DNA sequences of the structural genes. Three members of the chimpanzee triosephosphate isomerase (TPI) gene family, the functional transcription unit and two processed pseudogenes, were characterized by genomic blotting and DNA sequence analysis. The bona fide TPI gene spans 3.5 kb with seven exons and six introns, and is the first complete hominoid TPI gene sequenced. The gene exhibits a very high identity with the human and rhesus TPI genes. In particular, the polypeptides of 248 amino acids encoded by the chimpanzee and human TPI genes are identical, although the two coding regions differ in the third codon wobble positions for five amino acids. An Alu member occurs upstream from one of the processed pseudogenes, whereas an isolated endogenous retroviral long terminal repeat (HERV-K) occurs within the structural region of the other processed pseudogene. The ages of the processed pseudogenes were estimated to be 2.6 and 10.4 million years, implying that one was inserted into the genome before the divergence of the chimpanzee and human lineages, and the other inserted into the chimpanzee genome after the divergence.

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Krause, Mirja [Verfasser], Peter [Akademischer Betreuer] Neubauer, Rik [Akademischer Betreuer] Wierenga, and Juri [Akademischer Betreuer] Rappsilber. "Creating artificial sugar isomerases on the scaffold of a monomeric triosephosphate isomerase (A‐TIM) by protein engineering / Mirja Krause. Gutachter: Peter Neubauer ; Rik Wierenga ; Juri Rappsilber. Betreuer: Peter Neubauer ; Rik Wierenga." Berlin : Technische Universität Berlin, 2014. http://d-nb.info/1065665962/34.

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5

Lolis, Elias. "Crystallography and mutogenesis triosephosphate isomerase." Thesis, Massachusetts Institute of Technology, 1990. http://hdl.handle.net/1721.1/13959.

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Chang, Timothy C. "Evaluating the Role of Glu97 in Triosephosphate Isomerase." Thesis, California State University, Long Beach, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10979019.

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A comprehensive understanding of the design of proteins puts heavy emphasis on certain key residues. These key residues can often be identified by the level of conservation in nature, which acts as a reliable witness mark in order to study the pressures that select for residues which play a critical role in the function of the protein. In the case of triosephosphate isomerase (TIM), the fifth enzyme in glycolysis, the second-shell residue Glu97 has been found to be fully conserved across all known TIM sequences. Its proximity to the active site as well as several previous studies has pointed to a possible direct role in catalysis. However, the present study shows when Glu97 is mutated to Ala, Gln, and Asp in Trypanosoma brucei brucei (tbb) that the resulting effects on k_cat are small. Previous results from other studies that have observed larger mutational effects may be due to nearby non-conserved residues that are specific to the TIM homolog in which these studies are performed. The structural studies detailed here suggest that instead, Glu97 is involved in the structural stability of the enzyme, as well as participating in dimer formation. Size-exclusion chromatography analysis suggests that several tbbTIM mutants may in fact be monomeric.

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Fugtong, Nantana. "Physiological consequences of triosephosphate isomerase overproduction in Saccharomyces cerevisiae." Thesis, University of Edinburgh, 1995. http://hdl.handle.net/1842/20513.

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Triosephosphate isomerase was overproduced in yeast Saccharomyces cerevisiae by integration of extra copies of the TPI1 gene into the yeast chromosome. Specific enzyme activity was found to have increased between 2-7 fold above the wild-type level depending on the isolate used. The physiological consequences of enzyme overproduction by a factor of 2 and 7 were studied in aerobic batch cultures and aerobic glucose-limited chemostat cultures. Batch cultivation indicated that no significant difference in growth and metabolite production between overproducers and the reference could be detected. However, lower levels of three other glycolytic enzymes (PGK, PYK and HK) were found in a 7-fold TPI overproducer. Dilution rate profiles of TPI overproducers and the reference were studied in glucose-limited chemostat culture. The 7-fold TPI overproducer showed ethanol formation at D = 0.11 h^-1 where the 2-fold overproducer and the reference did not produce ethanol at all. Increase in dilution rate to 0.32 h^-1 resulted in increases of ethanol production rate as well as the rates of pyruvate and acetate production. The much more sensitive competitive chemostat cultures between TPI overproducers (2-fold or 7-fold) and the reference strain were studied using LEU2 gene as a detectable marker. The marker, however, showed strong effects on selection under all competitive chemostat studies. TPI activity was therefore used as a measure to determine the proportion of the strains in competition between the reference and TPI overproducers. Results showed that the 7-fold TPI overproducer was slightly favoured when competed against the 2-fold overproducer. However, this strain was found to be inferior to the reference strain. This is discussed as a possible effect of differences in URA3 gene copy number carried in these strains.

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Sun, An-Qiang. "How Do Enzymes Wear Out? Effects of Posttranslational Modifications on Structure and Stability of Proteins; The Triosephosphate Isomerase Model." Thesis, University of North Texas, 1991. https://digital.library.unt.edu/ark:/67531/metadc798116/.

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Triosephosphate isomerase (EC 5.3.1.1., TPI) undergoes specific posttranslational modifications (deamidation and oxidation) which are believed to initiate protein turnover by destabilization of the dimer. The crystal structures, amino acid sequences, and aging related changes of TPI from various species have been independently characterized by several laboratories. TPI has thus become the prototype enzyme for examining the initial steps in protein turnover. The binding of substrate enhances the specific deamidation of the mammalian enzyme, and a general mechanism of 'molecular wear and tear' [Gracy, R. W., Yiiksel, K. 0., Chapman, M. L., and Dimitrijevich, S. D. (1990) in Isozymes-Structure, Function and Use in Biology and Medicine (Ogita, Z-I., and Markert, C. L., Eds) pp. 787-817, Wiley-Liss, New York] has been proposed to explain how enzymes may wear out.

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Kursula, I. (Inari). "Crystallographic studies on the structure-function relationships in triosephosphate isomerase." Doctoral thesis, University of Oulu, 2003. http://urn.fi/urn:isbn:9514270096.

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Abstract The triosephosphate isomerase (TIM) barrel superfamily is a broad family of proteins, most of which are enzymes. At the amino-acid-sequence level, many of the members of this family share little, if any, homology. Yet, they adopt the same three-dimensional (βα)8 fold. The TIM barrel fold seems to be a good framework for many different kinds of enzymes, providing unique possibilities for both natural and human-designed evolution, as the catalytic center and the stabilizing features are separated to different ends of the barrel. Indeed, in the light of most recent studies, it seems likely that at least most of the different TIM barrel enzymes, catalyzing a huge variety of reactions, have evolved from a common ancestor. TIM can be considered a real text-book enzyme — its catalytic properties and stucture-function relationships have been studied for decades. Still, at present, we are quite far from understanding the structural features that make TIM and other enzymes such superior catalysts in both efficiency and precision. TIM is a dimeric enzyme that consists of two identical subunits of 250 residues. It catalyzes the interconversion of dihydroxyacetone phosphate and D-glyceraldehyde-3-phosphate in glycolysis. The basics of this reaction are well known, but there is ongoing discussion about the details of the proton transfer steps, and three alternative pathways have been suggested. In addition, it is a fascinating question how the enzyme succeeds in abstracting a highly stable proton from a carbon atom of the substrate. This study was undertaken to shed light on some of the questions concerning the structure-function relationships in TIM. The most important findings are the elucidation of the role of Asn11 as a catalytic residue and the meaning of the flexibility of both the catalytic Glu167 side chain as well as the substrate during catalysis, and the presence of a low-barrier hydrogen bond between Glu167 and a transition-state analogue, 2-phosphoglycolate. Furthermore, significant results were obtained on the importance of a conserved salt bridge, 20 Å away from the active site and the dimer interface, for the stability and folding of TIM as well as on the factors influencing the opening of the flexible loop 6 upon product release.

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Colquhoun, Anh N. "Investigating the Role of Glutamate 97 in Triosephosphate Isomerase from Homo sapiens." Thesis, California State University, Long Beach, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10976077.

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In spite of the advances made in experimental and mutational studies, understanding the importance of remote interactions is crucial for refining the knowledge of enzyme catalysis. In this study, a model system for Glu97 was developed in Homo sapiens triosephosphate isomerase ( hTIM) to investigate the energetic contribution and structural role of this fully conserved glutamate residue in the TIM-catalyzed isomerization reaction. Recombinant human triosephosphate isomerase (hTIM) was altered using site-directed mutagenesis, in which an aspartate, glutamine, or alanine residue was substituted for Glu97. In steady-state kinetics, the E97D variant exhibited the most significant catalytic activity while the E97Q enzyme was the least active. Observing both the forward and reverse directions of the TIM-catalyzed reaction, the results revealed that the enzymatic activity for E97D and E97A TIM was diminished by ~3-fold or less, and the rate was essentially unchanged for the E97D mutation. The E97Q mutant observed a greater rate effect, ~10-fold decrease in k_cat and ~20-fold decrease in catalytic efficiency (kcat/ K_M). To determine the conformational stability of the WT and mutant hTIM, unfolding of all four enzymes was monitored by circular dichroism, tryptophan and ANS fluorescence spectroscopy. The dimer stability was evaluated by gel-filtration analysis and the mutants showed similar chromatograms compared to that of the WT. The similar behavior observed for the WT and E97D suggests that the Asp mutation has little effect on catalysis, enzyme stability, and the unfolding pathway. On the contrary, the statistical significance observed in the E97Q and E97A mutants suggests that the Gln and Ala mutations affect the stability of the structure and may affect the unfolding pathway. Overall, these point-mutations support the model that remote interactions of Glu97 may have a modest role in catalysis. One explanation is that the direct role of Glu97 may have evolved in the human species and plays a less significant role compared to earlier species in evolution in which Glu97 mutations showed larger rate effects. Possibly, the network of unfavorable interactions is reduced and therefore, the mutational effect of Glu97 is less deleterious in hTIM.

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Books on the topic "Triosephosphate isomerases"

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Russell, Deanna L. Characterization of a retinol-induced triosephosphate isomerase cDNA isolated from rat testis using subtractive hybridization. 1994.

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Book chapters on the topic "Triosephosphate isomerases"

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Kamp, Marc Willem. "Triosephosphate Isomerase – Computational Studies." In Encyclopedia of Biophysics, 2658–59. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-16712-6_233.

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Blacklow, S. C., J. D. Hermes, and J. R. Knowles. "The Improvement of Catalytic Effectiveness of an Enzyme: Pseudorevertant Triosephosphate Isomerases Obtained by Random Mutagenesis of Catalytically Sluggish Mutants." In Protein Structure and Protein Engineering, 59–64. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-74173-9_7.

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Jimenez-Sandoval, Pedro, Eduardo Castro-Torres, Corina Diaz-Quezada, and Luis G. Brieba. "Crystallographic Studies of Triosephosphate Isomerase from Schistosoma mansoni." In Methods in Molecular Biology, 211–18. New York, NY: Springer US, 2020. http://dx.doi.org/10.1007/978-1-0716-0635-3_17.

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Nagase, Toshihiko, Toshihiro Sugiyama, Shigeki Higashiyama, Daitoku Sakamuro, Sumio Kawata, Seiichiro Tarui, and Naoyuki Taniguchi. "Identifications of Carbonic Anhydrase III and Triosephosphate Isomerase in the Liver Proteins in LEC Rats on Two-Dimensional Gel Electrophoresis." In The LEC Rat, 175–84. Tokyo: Springer Japan, 1991. http://dx.doi.org/10.1007/978-4-431-68153-3_20.

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Frey, Perry A., and Adrian D. Hegeman. "Isomerization." In Enzymatic Reaction Mechanisms. Oxford University Press, 2007. http://dx.doi.org/10.1093/oso/9780195122589.003.0011.

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Isomerization reactions are important in metabolism to potentiate further transformations that would otherwise be chemically impossible. A familiar example from glycolysis is phosphohexose isomerase, which catalyzes the interconversion of D-glusose-6-P and D-fructose-6-P. The formation of fructose-6-P makes it chemically feasible at a later step of glycolysis to cleave the six-carbon sugar into two three-carbon sugars, glyceraldehyde-3-P, and dihydroxyacetone-P by aldolase. No such cleavage of glucose-6-P into two three-carbon sugars is possible. The dihydroxyacetone-3-P is converted into glyceraldehyde-3-P by another isomerase, triosephosphate isomerase. In this way, glucose-6-P can be transformed into two molecules of glyceraldehyde-3-P, which can then be metabolized through glycolysis to pyruvate. Both reactions of phosphohexose and triosephosphate isomerases involve aldose/ketose interconversions and proceed by similar chemical mechanisms. Other important isomerases include phosphomutases, epimerases, racemases, and carbon-skeleton mutases, all of which have their roles in metabolism. The chemical mechanisms vary with the classes of isomerases and include enolizations, hydride transfer, oxidation/reduction, phosphotransfer, and radical rearrangements. In this chapter, we consider the mechanisms by which enzymes catalyze isomerization reaction. The interconversions of glucose-6-P and fructose-6-P and of the triose phosphates can be formulated chemically. The transformation in is an internal oxidation-reduction, in which the aldehyde group of the aldose is reduced and the neighboring alcoholic group is oxidized. This reaction can take place by either of two chemical mechanisms: an initial enolization at C2 to produce an enediolate intermediate that can be protonated at C1 to produce the product or a direct hydride transfer from C2 to C1. These mechanisms are outlined in scheme 7-1. Loss of the proton C2(H) by enolization in the upper pathway leads to the enediolate intermediate, and return of the proton to C1 (black arrows in scheme 7-1) leads to the ketose product. The hydride transfer mechanism in the lower pathway begins with the dissociation of the alcoholic proton to form the alcoholate intermediate. The alcoholate provides the driving force for the 1,2-hydride transfer (colored arrows in scheme 7-1) accompanied by protonation of the oxygen at C1. The two mechanisms require different hydrogen transfer regimes.

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"Triosephosphate Isomerase Deficiency (TPI1)." In Encyclopedia of Genetics, Genomics, Proteomics and Informatics, 2031. Dordrecht: Springer Netherlands, 2008. http://dx.doi.org/10.1007/978-1-4020-6754-9_17473.

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Zárate-Pérez, Francisco, María Elena Chánez-Cárdenas, and Edgar Vázquez-Contreras. "The Folding Pathway of Triosephosphate Isomerase." In Progress in Molecular Biology and Translational Science, 251–67. Elsevier, 2008. http://dx.doi.org/10.1016/s0079-6603(08)00407-8.

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Zanella, Alberto, and Paola Bianchi. "Erythrocyte enzymopathies." In Oxford Textbook of Medicine, edited by Chris Hatton and Deborah Hay, 5463–72. Oxford University Press, 2020. http://dx.doi.org/10.1093/med/9780198746690.003.0540.

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Numerous enzymes, including those of the hexose monophosphate and glycolytic pathways, are active in the red cell. They are required for the generation of ATP and the reductants NADH and NADPH. 2,3-Diphosphoglycerate, an intermediate of glucose metabolism, is a key regulator of the affinity of haemoglobin for oxygen, and accessory enzymes are also active for the synthesis of glutathione, disposal of oxygen free radicals, and for nucleotide metabolism. With the exception of heavy metal poisoning and rare cases of myelodysplasia, most red cell enzyme deficiency disorders are inherited. They may cause haematological abnormalities, (most commonly nonspherocytic haemolytic anaemias, but also rarely polycythaemia or methaemoglobinaemia, manifest with autosomal recessive or sex-linked inheritance), and may also be associated with nonhaematological disease when the defective enzyme is expressed throughout the body. Some may mirror important metabolic disorders, without producing haematological problems, making them of diagnostic value. Others are of no known clinical consequence. With rare exceptions, it is impossible to differentiate the enzymatic defects from one another by clinical or routine laboratory methods. Diagnosis depends on the combination of (1) accurate ascertainment of the family history; (2) morphological observations—these can determine whether haemolysis is present, rule out some causes of haemolysis (e.g. hereditary spherocytosis and other red blood cell membrane disorders), and diagnose pyrimidine 5′-nucleotidase deficiency (prominent red cell stippling); (3) estimation of red cell enzyme activity; and (4) molecular analysis. The most common red cell enzyme defects are glucose-6-phosphate dehydrogenase deficiency, pyruvate kinase deficiency, glucose-6-phosphate isomerase deficiency, pyrimidine 5′-nucleotidase deficiency—which may also induced by exposure to environmental lead—and triosephosphate isomerase deficiency.

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Cui, Qiang, and Martin Karplus. "Catalysis and Specificity in Enzymes: A Study of Triosephosphate Isomerase and Comparison with Methyl Glyoxal Synthase." In Protein Simulations, 315–72. Elsevier, 2003. http://dx.doi.org/10.1016/s0065-3233(03)66008-0.

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Conference papers on the topic "Triosephosphate isomerases"

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Zárate-Pérez, Francisco, Edgar Vázquez-Contreras, Leonardo Dagdug, and Leopoldo Gracía-Colin S. "The Oligomeric Nature of Triosephosphate Isomerase. Studies of Monomerization." In COMPLIFE 2007: The Third International Symposium on Computational Life Science. AIP, 2008. http://dx.doi.org/10.1063/1.2891415.

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Peräkylä, Mikael, and Tapani A. Pakkanen. "Ab initio model assembly study of the catalytic mechanism of triosephosphate isomerase (TIM)." In The first European conference on computational chemistry (E.C.C.C.1). AIP, 1995. http://dx.doi.org/10.1063/1.47648.

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Vázquez-Contreras, Edgar. "The Unfolding and Refolding Reactions of Triosephosphate Isomerase from Trypanosoma Cruzi Follow Similar Pathways. Guanidinium Hydrochloride Studies." In STATISTICAL PHYSICS AND BEYOND: 2nd Mexican Meeting on Mathematical and Experimental Physics. AIP, 2005. http://dx.doi.org/10.1063/1.1900497.

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