Structural highlights
Function
OTSA_ECOLI Catalyzes the transfer of glucose from UDP-glucose to glucose-6-phosphate to form alpha,alpha-1,1 trehalose-6-phosphate. Acts with retention of the anomeric configuration of the UDP-sugar donor. Essential for viability of the cells at low temperatures and at elevated osmotic strength.[1] [2] [3]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Trehalose is a nonreducing disaccharide that plays a major role in many organisms, most notably in survival and stress responses. In Mycobacterium tuberculosis, it plays a central role as the carbohydrate core of numerous immunogenic glycolipids including "cord factor" (trehalose 6,6'-dimycolate). The classical pathway for trehalose synthesis involves the condensation of UDP-glucose and glucose-6-phosphate to afford trehalose-6-phosphate, catalyzed by the retaining glycosyltransferase OtsA. The configurations of two anomeric positions are set simultaneously, resulting in the formation of a double glycoside. The three-dimensional structure of the Escherichia coli OtsA, in complex with both UDP and glucose-6-phosphate, reveals the active site at the interface of two beta/alpha/beta domains. The overall structure and the intimate details of the catalytic machinery reveal a striking similarity to glycogen phosphorylase, indicating a strong evolutionary link and suggesting a common catalytic mechanism.
Insights into trehalose synthesis provided by the structure of the retaining glucosyltransferase OtsA.,Gibson RP, Turkenburg JP, Charnock SJ, Lloyd R, Davies GJ Chem Biol. 2002 Dec;9(12):1337-46. PMID:12498887[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Kaasen I, Falkenberg P, Styrvold OB, Strom AR. Molecular cloning and physical mapping of the otsBA genes, which encode the osmoregulatory trehalose pathway of Escherichia coli: evidence that transcription is activated by katF (AppR) J Bacteriol. 1992 Feb;174(3):889-98. PMID:1310094
- ↑ Giaever HM, Styrvold OB, Kaasen I, Strom AR. Biochemical and genetic characterization of osmoregulatory trehalose synthesis in Escherichia coli. J Bacteriol. 1988 Jun;170(6):2841-9. PMID:3131312
- ↑ Kandror O, DeLeon A, Goldberg AL. Trehalose synthesis is induced upon exposure of Escherichia coli to cold and is essential for viability at low temperatures. Proc Natl Acad Sci U S A. 2002 Jul 23;99(15):9727-32. Epub 2002 Jul 8. PMID:12105274 doi:http://dx.doi.org/10.1073/pnas.142314099
- ↑ Gibson RP, Turkenburg JP, Charnock SJ, Lloyd R, Davies GJ. Insights into trehalose synthesis provided by the structure of the retaining glucosyltransferase OtsA. Chem Biol. 2002 Dec;9(12):1337-46. PMID:12498887
