Crystal structure of homoserine O ‐succinyltransferase from Bacillus cereus at 2.4 Å resolution

作者：Chloé Zubieta, Sanjeev Krishna, Daniel McMullan, Mitchell D. Miller, Polat Abdubek, Sanjay Agarwalla, Eileen Ambing, Tamara Astakhova, Herbert L. Axelrod, Dennis Carlton, Hsiu‐Ju Chiu, Thomas Clayton, Marc C. Deller, Michael DiDonato, Lian Duan, Marc‐André Elsliger, Slawomir K. Grzechnik, Joanna Hale, Eric Hampton, Gye Won Han, Justin Haugen, Lukasz Jaroszewski, Kevin K. Jin, Heath E. Klock, Mark W. Knuth, Eric Koesema, Abhinav Kumar, David Marciano, Andrew T. Morse, Edward Nigoghossian, Silvya Oommachen, Ron Reyes, Christopher L. Rife, Henry van den Bedem, Dana Weekes, Aprilfawn White, Qingping Xu, Keith O. Hodgson, John Wooley, Ashley M. Deacon, Adam Godzik, Scott A. Lesley, Ian A. Wilson · 发表于：Proteins Structure Function and Bioinformatics · 年份：2007 · DOI：10.1002/prot.21208 · 被引用次数：16 · 研究领域：Enzyme Structure and Function、Biochemical and Molecular Research、RNA modifications and cancer

Methionine is one of 10 essential dietary amino acids in mammals; however, most bacteria, fungi, and plants are able to synthesize methionine de novo from aspartic acid. While the methionine biosynthetic pathway shares many common steps in microorganisms and plants, the pathway diverges in their activation of homoserine,1-4 the initial step of methionine biosynthesis. Bacteria, fungi, and archaea acylate homoserine, but most plants phosphorylate the γ-hydroxyl of homoserine for activation.5 The acylation reactions in bacterial and fungal systems utilize very similar substrates and most likely follow similar reaction mechanisms.6 Upon acylation, the acylhomoserine is shuttled to cystathionine γ-synthase for condensation with cysteine to form cystathionine. Subsequently, the cystathionine is hydrolyzed to form homocysteine, which is then methylated to produce methionine.7 In bacteria, two distinct families of enzymes are responsible for the activation of homoserine. Succinylation of homoserine in some bacteria, such as Escherichia coli and Bacillus cereus, is catalyzed by homoserine O-succinyltransferase (HTS; E.C 2.3.1.46), while other bacteria, such as Haemophilus influenzae, Pseudomonas aeruginosa, and Mycobacterium tuberculosis, acetylate homoserine via homoserine O-acetyltransferase (HTA; E.C 2.3.1.31). HTAs and HTSs fall into two distinct families based on primary sequence, but membership in a family does not necessarily predict substrate preference or specificity.4 While...