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Su L, Lv M, Kyeremeh K, Deng Z, Deng H, Yu Y. A ThDP-dependent enzymatic carboligation reaction involved in Neocarazostatin A tricyclic carbazole formation. Org Biomol Chem 2018; 14:8679-8684. [PMID: 27714211 DOI: 10.1039/c6ob01651k] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Although the biosynthetic pathway of Neocarazostatin A (1) has been identified, the detailed enzymatic reactions underlying the assembly of the carbazole ring still remain largely unknown. We demonstrate here that NzsH, a putative thiamine diphosphate dependent enzyme, can catalyze an acyloin coupling reaction between indole-3-pyruvate and pyruvate to generate a β-ketoacid intermediate. Our findings thus shed light on further characterization of the unusual biosynthetic pathway of the bacterial tricyclic carbazole alkaloids.
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Affiliation(s)
- Li Su
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education), School of Pharmaceutical Sciences, Wuhan University, 185 East Lake Road, Wuhan 430071, P.R. China.
| | - Meinan Lv
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education), School of Pharmaceutical Sciences, Wuhan University, 185 East Lake Road, Wuhan 430071, P.R. China.
| | - Kwaku Kyeremeh
- Department of Chemistry, University of Ghana, P.O. Box LG56, Legon-Accra, Ghana
| | - Zixin Deng
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education), School of Pharmaceutical Sciences, Wuhan University, 185 East Lake Road, Wuhan 430071, P.R. China.
| | - Hai Deng
- Marine Biodiscovery Centre, Department of Chemistry, University of Aberdeen, Aberdeen AB24 3UE, Scotland, UK
| | - Yi Yu
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education), School of Pharmaceutical Sciences, Wuhan University, 185 East Lake Road, Wuhan 430071, P.R. China.
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2
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Zhang J, Liu Y. Theoretical study of the catalytic mechanism of glyoxylate carboligase and its mutant V51E. Theor Chem Acc 2017. [DOI: 10.1007/s00214-017-2079-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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3
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Yan Z, Maruyama A, Arakawa T, Fushinobu S, Wakagi T. Crystal structures of archaeal 2-oxoacid:ferredoxin oxidoreductases from Sulfolobus tokodaii. Sci Rep 2016; 6:33061. [PMID: 27619895 PMCID: PMC5020499 DOI: 10.1038/srep33061] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 08/16/2016] [Indexed: 11/22/2022] Open
Abstract
As the first three-dimensional structure of the two-subunit type 2-oxoacid:ferredoxin oxidoreductases (OFOR) from archaea, we solved the crystal structures of STK_23000/STK_22980 (StOFOR1) and STK_24350/STK_24330 (StOFOR2) from Sulfolobus tokodaii. They showed similar overall structures, consisting of two a- and b-subunit heterodimers containing thiamin pyrophosphate (TPP) cofactor and [4Fe-4S] cluster, but lack an intramolecular ferredoxin domain. Unlike other OFORs, StOFORs can utilize both pyruvate and 2-oxoglutarate, playing a key role in the central metabolism. In the structure of StOFOR2 in unreacted pyruvate complex form, carboxylate group of pyruvate is recognized by Arg344 and Thr257 from the a-subunit, which are conserved in pyruvate:ferredoxin oxidoreductase from Desulfovbrio africanus (DaPFOR). In the structure of StOFOR1 co-crystallized with 2-oxobutyrate, electron density corresponding to a 1-hydroxypropyl group (post-decarboxylation state) was observed at the thiazole ring of TPP. The binding pockets of the StOFORs surrounding the methyl or propyl group of the ligands are wider than that of DaPFOR. Mutational analyses indicated that several residues were responsible for the broad 2-oxoacid specificity of StOFORs. We also constructed a possible complex structural model by placing a Zn(2+)-containing dicluster ferredoxin of S. tokodaii into the large pocket of StOFOR2, providing insight into the electron transfer between the two redox proteins.
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Affiliation(s)
- Zhen Yan
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Akane Maruyama
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Takatoshi Arakawa
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Shinya Fushinobu
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Takayoshi Wakagi
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
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4
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Liu Y, Li Y, Wang X. Acetohydroxyacid synthases: evolution, structure, and function. Appl Microbiol Biotechnol 2016; 100:8633-49. [DOI: 10.1007/s00253-016-7809-9] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 07/28/2016] [Accepted: 08/12/2016] [Indexed: 10/21/2022]
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5
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Mariadasse R, Biswal J, Jayaprakash P, Rao GR, Choubey SK, Rajendran S, Jeyakanthan J. Mechanical insights of oxythiamine compound as potent inhibitor for human transketolase-like protein 1 (TKTL1 protein). J Recept Signal Transduct Res 2015; 36:233-42. [PMID: 26481897 DOI: 10.3109/10799893.2015.1080272] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Transketolase is a connecting link between glycolytic and pentose phosphate pathway, which is considered as the rate-limiting step due to synthesis of large number of ATP molecule and it can be proposed as a plausible target facilitating the growth of cancerous cells suggesting its potential role in cancer. Oxythiamine, an antimetabolite has been proved to be an efficient anticancerous compound in vitro, but its structural elucidation of the inhibitory mechanism has not yet been done against the human transketolase-like 1 protein (TKTL1). The three-dimensional (3D) structure of TKTL1 protein was modeled and subjected for refinement, stability and validation. Based on the reported homologs of transketolase (TKT), the active site residues His46, Ser49, Ser52, Ser53, Ile56, Leu82, Lys84, Leu123, Ser125, Glu128, Asp154, His160, Thr216 and Lys218 were identified and considered for molecular-modeling studies. Docking studies reveal the H-bond interactions with residues Ser49 and Lys218 that could play a major role in the activity of TKTL1. Molecular dynamics (MD) simulation study was performed to reveal the comparative stability of both native and complex forms of TKTL1. MD trajectory at 30 ns, confirm the role of active site residues Ser49, Lys84, Glu128, His160 and Lys218 in suppressing the activity of TKTL1. Glu128 is observed to be the most important residue for deprotonation state of the aminopyrimidine moiety and preferred to be the site of inhibitory action. Thus, the proposed mechanism of inhibition through in silico studies would pave the way for structure-oriented drug designing against cancer.
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Affiliation(s)
- Richard Mariadasse
- a Department of Bioinformatics , Structural Biology and Bio-Computing Laboratory, Alagappa University , Karaikudi , Tamil Nadu , India
| | - Jayashree Biswal
- a Department of Bioinformatics , Structural Biology and Bio-Computing Laboratory, Alagappa University , Karaikudi , Tamil Nadu , India
| | - Prajisha Jayaprakash
- a Department of Bioinformatics , Structural Biology and Bio-Computing Laboratory, Alagappa University , Karaikudi , Tamil Nadu , India
| | - Guru Raj Rao
- a Department of Bioinformatics , Structural Biology and Bio-Computing Laboratory, Alagappa University , Karaikudi , Tamil Nadu , India
| | - Sanjay Kumar Choubey
- a Department of Bioinformatics , Structural Biology and Bio-Computing Laboratory, Alagappa University , Karaikudi , Tamil Nadu , India
| | - Santhosh Rajendran
- a Department of Bioinformatics , Structural Biology and Bio-Computing Laboratory, Alagappa University , Karaikudi , Tamil Nadu , India
| | - Jeyaraman Jeyakanthan
- a Department of Bioinformatics , Structural Biology and Bio-Computing Laboratory, Alagappa University , Karaikudi , Tamil Nadu , India
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6
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Sheng X, Liu Y, Zhang R. A theoretical study of the catalytic mechanism of oxalyl-CoA decarboxylase, an enzyme for treating urolithiasis. RSC Adv 2014. [DOI: 10.1039/c4ra03611e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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7
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The modular structure of ThDP-dependent enzymes. Proteins 2014; 82:2523-37. [DOI: 10.1002/prot.24615] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Revised: 05/06/2014] [Accepted: 05/20/2014] [Indexed: 01/12/2023]
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8
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Patel H, Shim DJ, Farinas ET, Jordan F. Investigation of the donor and acceptor range for chiral carboligation catalyzed by the E1 component of the 2-oxoglutarate dehydrogenase complex. ACTA ACUST UNITED AC 2013; 98. [PMID: 24277992 DOI: 10.1016/j.molcatb.2013.09.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The potential of thiamin diphosphate (ThDP)-dependent enzymes to catalyze C-C bond forming (carboligase) reactions with high enantiomeric excess has been recognized for many years. Here we report the application of the E1 component of the Escherichia coli 2-oxoglutarate dehydrogenase multienzyme complex in the synthesis of chiral compounds with multiple functional groups in good yield and high enantiomeric excess, by varying both the donor substrate (different 2-oxo acids) and the acceptor substrate (glyoxylate, ethyl glyoxylate and methyl glyoxal). Major findings include the demonstration that the enzyme can accept 2-oxovalerate and 2-oxoisovalerate in addition to its natural substrate 2-oxoglutarate, and that the tested acceptors are also acceptable in the carboligation reaction, thereby very much expanding the repertory of the enzyme in chiral synthesis.
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Affiliation(s)
- Hetalben Patel
- Department of Chemistry, Rutgers University, Newark, NJ 07102
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10
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Sheng X, Liu Y. Theoretical study of the catalytic mechanism of E1 subunit of pyruvate dehydrogenase multienzyme complex from Bacillus stearothermophilus. Biochemistry 2013; 52:8079-93. [PMID: 24171427 DOI: 10.1021/bi400577f] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Pyruvate dehydrogenase multienzyme complex (PDHc) is a member of a family of 2-oxo acid dehydrogenase (OADH) multienzyme complexes involved in several central points of oxidative metabolism, and the E1 subunit is the most important component in the entire PDHc catalytic system, which catalyzes the reversible transfer of an acetyl group from a pyruvate to the lipoyl group of E2 subunit lipoly domain. In this article, the catalytic mechanism of the E1 subunit has been systematically studied using density functional theory (DFT). Four possible pathways with different general acid/base catalysts in decarboxylation and reductive acylation processes were explored. Our calculation results indicate that the 4'-amino pyrimidine of ThDP and residue His128 are the most likely proton donors in the decarboxylation and reductive acylation processes, respectively. During the reaction, each C-C and C-S bond formation or cleavage process, except for the liberation of CO2, is always accompanied by a proton transfer between the substrates and proton donors. The liberation of CO2 is calculated to be the rate-limiting step for the overall reaction, with an energy barrier of 13.57 kcal/mol. The decarboxylation process is endothermic by 5.32 kcal/mol, whereas the reductive acylation process is exothermic with a value of 5.74 kcal/mol. The assignment of protonation states of the surrounding residues can greatly influence the reaction. Residues His128 and His271 play roles in positioning the first substrate pyruvate and second substrate lipoyl group, respectively.
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Affiliation(s)
- Xiang Sheng
- Key Laboratory of Theoretical and Computational Chemistry in Universities of Shandong, School of Chemistry and Chemical Engineering, Shandong University , Jinan, Shandong 250100, China
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11
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Baig IA, Gedi V, Lee SC, Koh SH, Yoon MY. Role of a highly conserved proline-126 in ThDP binding of Mycobacterium tuberculosis acetohydroxyacid synthase. Enzyme Microb Technol 2013; 53:243-9. [PMID: 23931689 DOI: 10.1016/j.enzmictec.2013.05.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 05/12/2013] [Accepted: 05/14/2013] [Indexed: 11/30/2022]
Abstract
Acetohydroxyacid synthase (AHAS) of Mycobacterium tuberculosis is a promising target for the development of anti-tuberculosis agents. With the absence of an available bacterial AHAS crystal structure, that of M. tuberculosis, site-directed mutagenesis has been a useful tool for determining its structural and functional features. In this study, a highly conserved proline residue (P126 of M. tuberculosis AHAS) was selected, and the possible role was evaluated by site-directed mutagenesis. P126 was replaced by valine, threonine, alanine, and glutamate to yield P126V, P126T, P126A, and P126E, respectively. All variants were expressed in their soluble forms in Escherichia coli and purified to near homogeneity. The molecular mass (SDS-PAGE) of the purified variants was ∼68 kDa, which is similar to that of wild-type AHAS. The P126V, P126T, and P126A variants exhibited significantly lower activity than wild-type AHAS, whereas P126E was inactive under the tested assay conditions. Furthermore, the P126V and P126T variants showed a significantly decreased preference toward pyruvate and ThDP as substrate and cofactor respectively, whereas the P126A showed similar kinetics to that of wild-type AHAS. Like in AHAS from yeast Saccharomyces cerevisiae (PDB ID: 1N0H), residue P126 is located in the ThDP binding pocket of M. tuberculosis AHAS homology model. Collectively, these results suggest that the conserved P126 plays a significant role in the ThDP binding of M. tuberculosis AHAS.
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12
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Uversky VN. The alphabet of intrinsic disorder: II. Various roles of glutamic acid in ordered and intrinsically disordered proteins. INTRINSICALLY DISORDERED PROTEINS 2013; 1:e24684. [PMID: 28516010 PMCID: PMC5424795 DOI: 10.4161/idp.24684] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/21/2013] [Revised: 03/27/2013] [Accepted: 04/12/2013] [Indexed: 11/19/2022]
Abstract
The ability of a protein to fold into unique functional state or to stay intrinsically disordered is encoded in its amino acid sequence. Both ordered and intrinsically disordered proteins (IDPs) are natural polypeptides that use the same arsenal of 20 proteinogenic amino acid residues as their major building blocks. The exceptional structural plasticity of IDPs, their capability to exist as heterogeneous structural ensembles and their wide array of important disorder-based biological functions that complements functional repertoire of ordered proteins are all rooted within the peculiar differential usage of these building blocks by ordered proteins and IDPs. In fact, some residues (so-called disorder-promoting residues) are noticeably more common in IDPs than in sequences of ordered proteins, which, in their turn, are enriched in several order-promoting residues. Furthermore, residues can be arranged according to their “disorder promoting potencies,” which are evaluated based on the relative abundances of various amino acids in ordered and disordered proteins. This review continues a series of publications on the roles of different amino acids in defining the phenomenon of protein intrinsic disorder and concerns glutamic acid, which is the second most disorder-promoting residue.
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Affiliation(s)
- Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute; College of Medicine; University of South Florida; Tampa, FL USA.,Institute for Biological Instrumentation; Russian Academy of Sciences; Moscow, Russia
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Lee MY, Lee SC, Cho JH, Ryu SE, Koo BS, Yoon MY. Role of a Highly Conserved and Catalytically Important Glutamate-49 in the Enterococcus faecalis Acetolactate Synthase. B KOREAN CHEM SOC 2013. [DOI: 10.5012/bkcs.2013.34.2.669] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Meshalkina LE, Drutsa VL, Koroleva ON, Solovjeva ON, Kochetov GA. Is transketolase-like protein, TKTL1, transketolase? Biochim Biophys Acta Mol Basis Dis 2012; 1832:387-90. [PMID: 23261987 DOI: 10.1016/j.bbadis.2012.12.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Revised: 11/30/2012] [Accepted: 12/10/2012] [Indexed: 10/27/2022]
Abstract
Until recently it was assumed that the transketolase-like protein (TKTL1) detected in the tumor tissue, is catalytically active mutant form of human transketolase (hTKT). Human TKT shares 61% sequence identity with TKTL1. And the two proteins are 77% homologous at the amino acid level. The major difference is the absence of 38 amino acid residues in the N-terminal region of TKTL1. Site-specific mutagenesis was used for modifying hTKT gene; the resulting construct had a 114-bp deletion corresponding to a deletion of 38 amino acid residues in hTKT protein. Wild type hTKT and mutant variant (DhTKT) were expressed in Escherichia coli and isolated using Ni-agarose affinity chromatography. We have demonstrated here that DhTKT is devoid of transketolase activity and lacks bound thiamine diphosphate (ThDP). In view of these results, it is unlikely that TKTL1 may be a ThDP-dependent protein capable of catalyzing the transketolase reaction, as hypothesized previously.
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Affiliation(s)
- Ludmilla E Meshalkina
- Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow, Russia.
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Vogel C, Widmann M, Pohl M, Pleiss J. A standard numbering scheme for thiamine diphosphate-dependent decarboxylases. BMC BIOCHEMISTRY 2012; 13:24. [PMID: 23157214 PMCID: PMC3534367 DOI: 10.1186/1471-2091-13-24] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Accepted: 11/08/2012] [Indexed: 01/05/2023]
Abstract
Background Standard numbering schemes for families of homologous proteins allow for the unambiguous identification of functionally and structurally relevant residues, to communicate results on mutations, and to systematically analyse sequence-function relationships in protein families. Standard numbering schemes have been successfully implemented for several protein families, including lactamases and antibodies, whereas a numbering scheme for the structural family of thiamine-diphosphate (ThDP) -dependent decarboxylases, a large subfamily of the class of ThDP-dependent enzymes encompassing pyruvate-, benzoylformate-, 2-oxo acid-, indolpyruvate- and phenylpyruvate decarboxylases, benzaldehyde lyase, acetohydroxyacid synthases and 2-succinyl-5-enolpyruvyl-6-hydroxy-3-cyclohexadiene-1-carboxylate synthase (MenD) is still missing. Despite a high structural similarity between the members of the ThDP-dependent decarboxylases, their sequences are diverse and make a pairwise sequence comparison of protein family members difficult. Results We developed and validated a standard numbering scheme for the family of ThDP-dependent decarboxylases. A profile hidden Markov model (HMM) was created using a set of representative sequences from the family of ThDP-dependent decarboxylases. The pyruvate decarboxylase from S. cerevisiae (PDB: 2VK8) was chosen as a reference because it is a well characterized enzyme. The crystal structure with the PDB identifier 2VK8 encompasses the structure of the ScPDC mutant E477Q, the cofactors ThDP and Mg2+ as well as the substrate analogue (2S)-2-hydroxypropanoic acid. The absolute numbering of this reference sequence was transferred to all members of the ThDP-dependent decarboxylase protein family. Subsequently, the numbering scheme was integrated into the already established Thiamine-diphosphate dependent Enzyme Engineering Database (TEED) and was used to systematically analyze functionally and structurally relevant positions in the superfamily of ThDP-dependent decarboxylases. Conclusions The numbering scheme serves as a tool for the reliable sequence alignment of ThDP-dependent decarboxylases and the unambiguous identification and communication of corresponding positions. Thus, it is the basis for the systematic and automated analysis of sequence-encoded properties such as structural and functional relevance of amino acid positions, because the analysis of conserved positions, the identification of correlated mutations and the determination of subfamily specific amino acid distributions depend on reliable multisequence alignments and the unambiguous identification of the alignment columns. The method is reliable and robust and can easily be adapted to further protein families.
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Affiliation(s)
- Constantin Vogel
- Institute of Technical Biochemistry, University of Stuttgart, Allmandring 31, Stuttgart, 70569, Germany
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Nemeria N, Binshtein E, Patel H, Balakrishnan A, Vered I, Shaanan B, Barak Z, Chipman D, Jordan F. Glyoxylate carboligase: a unique thiamin diphosphate-dependent enzyme that can cycle between the 4'-aminopyrimidinium and 1',4'-iminopyrimidine tautomeric forms in the absence of the conserved glutamate. Biochemistry 2012; 51:7940-52. [PMID: 22970650 DOI: 10.1021/bi300893v] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Glyoxylate carboligase (GCL) is a thiamin diphosphate (ThDP)-dependent enzyme, which catalyzes the decarboxylation of glyoxylate and ligation to a second molecule of glyoxylate to form tartronate semialdehyde (TSA). This enzyme is unique among ThDP enzymes in that it lacks a conserved glutamate near the N1' atom of ThDP (replaced by Val51) or any other potential acid-base side chains near ThDP. The V51D substitution shifts the pH optimum to 6.0-6.2 (pK(a) of 6.2) for TSA formation from pH 7.0-7.7 in wild-type GCL. This pK(a) is similar to the pK(a) of 6.1 for the 1',4'-iminopyrimidine (IP)-4'-aminopyrimidinium (APH(+)) protonic equilibrium, suggesting that the same groups control both ThDP protonation and TSA formation. The key covalent ThDP-bound intermediates were identified on V51D GCL by a combination of steady-state and stopped-flow circular dichroism methods, yielding rate constants for their formation and decomposition. It was demonstrated that active center variants with substitution at I393 could synthesize (S)-acetolactate from pyruvate solely, and acetylglycolate derived from pyruvate as the acetyl donor and glyoxylate as the acceptor, implying that this substitutent favored pyruvate as the donor in carboligase reactions. Consistent with these observations, the I393A GLC variants could stabilize the predecarboxylation intermediate analogues derived from acetylphosphinate, propionylphosphinate, and methyl acetylphosphonate in their IP tautomeric forms notwithstanding the absence of the conserved glutamate. The role of the residue at the position occupied typically by the conserved Glu controls the pH dependence of kinetic parameters, while the entire reaction sequence could be catalyzed by ThDP itself, once the APH(+) form is accessible.
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Affiliation(s)
- Natalia Nemeria
- Department of Life Sciences, Ben-Gurion University , P.O. Box 653, Beer-Sheva 84105, Israel
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Belenky I, Steinmetz A, Vyazmensky M, Barak Z, Tittmann K, Chipman DM. Many of the functional differences between acetohydroxyacid synthase (AHAS) isozyme I and other AHASs are a result of the rapid formation and breakdown of the covalent acetolactate-thiamin diphosphate adduct in AHAS I. FEBS J 2012; 279:1967-79. [DOI: 10.1111/j.1742-4658.2012.08577.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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18
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Maslova AO, Meshalkina LE, Kochetov GA. Computer modeling of transketolase-like protein, TKTL1, a marker of certain tumor tissues. BIOCHEMISTRY (MOSCOW) 2012; 77:296-9. [DOI: 10.1134/s000629791203008x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Barak Z, Chipman DM. Allosteric regulation in Acetohydroxyacid Synthases (AHASs) – Different structures and kinetic behavior in isozymes in the same organisms. Arch Biochem Biophys 2012; 519:167-74. [DOI: 10.1016/j.abb.2011.11.025] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Revised: 11/25/2011] [Accepted: 11/29/2011] [Indexed: 10/14/2022]
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20
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Gedi V, Yoon MY. Bacterial acetohydroxyacid synthase and its inhibitors - a summary of their structure, biological activity and current status. FEBS J 2012; 279:946-63. [DOI: 10.1111/j.1742-4658.2012.08505.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Vyazmensky M, Steinmetz A, Meyer D, Golbik R, Barak Z, Tittmann K, Chipman DM. Significant Catalytic Roles for Glu47 and Gln 110 in All Four of the C−C Bond-Making and -Breaking Steps of the Reactions of Acetohydroxyacid Synthase II. Biochemistry 2011; 50:3250-60. [DOI: 10.1021/bi102051h] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Maria Vyazmensky
- Ben-Gurion University of the Negev, Department of Life Sciences, Beer-Sheva 84105, Israel
| | - Andrea Steinmetz
- Georg-August University Göttingen, Albrecht-von-Haller-Institute and Göttingen Centre for Molecular Biosciences, Ernst-Caspari-Haus, Department of Bioanalytics, Justus-von-Liebig Weg 11, 37077 Göttingen, Germany
- Martin-Luther University Halle-Wittenberg, Institute for Biochemistry and Biotechnology, Kurt-Mothes-Strasse 3, 06120 Halle/Saale, Germany
| | - Danilo Meyer
- Georg-August University Göttingen, Albrecht-von-Haller-Institute and Göttingen Centre for Molecular Biosciences, Ernst-Caspari-Haus, Department of Bioanalytics, Justus-von-Liebig Weg 11, 37077 Göttingen, Germany
- Martin-Luther University Halle-Wittenberg, Institute for Biochemistry and Biotechnology, Kurt-Mothes-Strasse 3, 06120 Halle/Saale, Germany
| | - Ralph Golbik
- Martin-Luther University Halle-Wittenberg, Institute for Biochemistry and Biotechnology, Kurt-Mothes-Strasse 3, 06120 Halle/Saale, Germany
| | - Ze'ev Barak
- Ben-Gurion University of the Negev, Department of Life Sciences, Beer-Sheva 84105, Israel
| | - Kai Tittmann
- Georg-August University Göttingen, Albrecht-von-Haller-Institute and Göttingen Centre for Molecular Biosciences, Ernst-Caspari-Haus, Department of Bioanalytics, Justus-von-Liebig Weg 11, 37077 Göttingen, Germany
- Martin-Luther University Halle-Wittenberg, Institute for Biochemistry and Biotechnology, Kurt-Mothes-Strasse 3, 06120 Halle/Saale, Germany
| | - David M. Chipman
- Ben-Gurion University of the Negev, Department of Life Sciences, Beer-Sheva 84105, Israel
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Slutzker A, Vyazmensky M, Chipman DM, Barak Z. Role of the C-terminal domain of the regulatory subunit of AHAS isozyme III: Use of random mutagenesis with in vivo reconstitution (REM-ivrs). BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2011; 1814:449-55. [DOI: 10.1016/j.bbapap.2011.01.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Revised: 12/06/2010] [Accepted: 01/04/2011] [Indexed: 11/28/2022]
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23
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Crystal structure of Bifidobacterium Longum phosphoketolase; key enzyme for glucose metabolism in Bifidobacterium. FEBS Lett 2010; 584:3855-61. [PMID: 20674574 DOI: 10.1016/j.febslet.2010.07.043] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2010] [Revised: 07/09/2010] [Accepted: 07/23/2010] [Indexed: 11/22/2022]
Abstract
The crystal structure of Bifidobacterium longum phosphoketolase, a thiamine diphosphate (TPP) dependent enzyme, has been determined at 2.2A resolution. The enzyme is a dimer with the active sites located at the interface between the two identical subunits with molecular mass of 92.5 kDa. The bound TPP is almost completely shielded from solvent except for the catalytically important C2-carbon of the thiazolium ring, which can be accessed by a substrate sugar through a narrow funnel-shaped channel. In silico docking studies of B. longum phosphoketolase with its substrate enable us to propose a model for substrate binding.
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