3b18

From Proteopedia

Rv0098 of Mycobacterium tuberculosis with ordered loop between beta-4 and beta-5

Structural highlights

3b18 is a 1 chain structure with sequence from Mycobacterium tuberculosis. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Method:	X-ray diffraction, Resolution 2.75Å
Ligands:
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

INLPD_MYCTU Involved in the biosynthesis of a unique class of isonitrile lipopeptides (INLPs) that seem to function as virulence factors in M.tuberculosis and to play a role in metal acquisition (PubMed:28634299). Catalyzes a Michael addition of glycine to the beta-position of an alpha,beta-unsaturated fatty acyl-[ACP], producing a (3R)-3-[(carboxymethyl)amino]fatty acid. Acts on the (2E)-decenoyl moiety loaded on the acyl-carrier protein (ACP) Rv0100, forming the product (3R)-3-[(carboxymethyl)amino]decanoate released from the ACP (By similarity). Displays thioesterase activity with a preference for long chain fatty acyl groups; in vitro, cleaves the thioester linkage of palmitoyl-CoA, stearoyl-CoA, lauroyl-CoA and hexanoyl-CoA (PubMed:17524985). Contains low levels of trans-enoyl hydratase activity (PubMed:19136596).[UniProtKB:B2HKM2]^[1] ^[2] ^[3]

Publication Abstract from PubMed

The crystal structure of Rv0098, a long-chain fatty acyl-CoA thioesterase from Mycobacterium tuberculosis with bound dodecanoic acid at the active site provided insights into the mode of substrate binding but did not reveal the structural basis of substrate specificities of varying chain length. Molecular dynamics studies demonstrated that certain residues of the substrate binding tunnel are flexible and thus modulate the length of the tunnel. The flexibility of the loop at the base of the tunnel was also found to be important for determining the length of the tunnel for accommodating appropriate substrates. A combination of crystallographic and molecular dynamics studies thus explained the structural basis of accommodating long chain substrates by Rv0098 of M. tuberculosis.

Insights into the Substrate Specificity of a Thioesterase Rv0098 of Mycobacterium Tuberculosis through X-ray Crystallographic and Molecular Dynamics Studies.,Maity K, Bajaj P, Surolia N, Surolia A, Suguna K J Biomol Struct Dyn. 2012 Apr;29(5):973-83. PMID:22292955^[4]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Wang F, Langley R, Gulten G, Wang L, Sacchettini JC. Identification of a type III thioesterase reveals the function of an operon crucial for Mtb virulence. Chem Biol. 2007 May;14(5):543-51. PMID:17524985 doi:http://dx.doi.org/S1074-5521(07)00141-X
↑ Gurvitz A, Hiltunen JK, Kastaniotis AJ. Heterologous expression of mycobacterial proteins in Saccharomyces cerevisiae reveals two physiologically functional 3-hydroxyacyl-thioester dehydratases, HtdX and HtdY, in addition to HadABC and HtdZ. J Bacteriol. 2009 Apr;191(8):2683-90. doi: 10.1128/JB.01046-08. Epub 2009 Jan 9. PMID:19136596 doi:http://dx.doi.org/10.1128/JB.01046-08
↑ Harris NC, Sato M, Herman NA, Twigg F, Cai W, Liu J, Zhu X, Downey J, Khalaf R, Martin J, Koshino H, Zhang W. Biosynthesis of isonitrile lipopeptides by conserved nonribosomal peptide synthetase gene clusters in Actinobacteria. Proc Natl Acad Sci U S A. 2017 Jul 3;114(27):7025-7030. PMID:28634299 doi:10.1073/pnas.1705016114
↑ Maity K, Bajaj P, Surolia N, Surolia A, Suguna K. Insights into the Substrate Specificity of a Thioesterase Rv0098 of Mycobacterium Tuberculosis through X-ray Crystallographic and Molecular Dynamics Studies. J Biomol Struct Dyn. 2012 Apr;29(5):973-83. PMID:22292955