Thiolase: A Versatile Biocatalyst Employing CoA-Thioester Chemistry for Making and Breaking C-C Bonds

Annu Rev Biochem. 2023 Apr 17. doi: 10.1146/annurev-biochem-052521-033746. Online ahead of print.ABSTRACTThiolases are CoA-dependent enzymes that catalyze the thiolytic cleavage of 3-ketoacyl-CoA, as well as its reverse reaction, which is the thioester-dependent Claisen condensation reaction. Thiolases are dimers or tetramers (dimers of dimers). All thiolases have two reactive cysteines: (a) a nucleophilic cysteine, which forms a covalent intermediate, and (b) an acid/base cysteine. The best characterized thiolase is the Zoogloea ramigera thiolase, which is a bacterial biosynthetic thiolase belonging to the CT-thiolase subfamily. The thiolase active site is also characterized by two oxyanion holes, two active site waters, and four catalytic loops with characteristic amino acid sequence fingerprints. Three thiolase subfamilies can be identified, each characterized by a unique sequence fingerprint for one of their catalytic loops, which causes unique active site properties. Recent insights concerning the thiolase reaction mechanism, as obtained from recent structural studies, as well as from classical and recent enzymological studies, are addressed, and open questions are discussed. Expected final online publication date for the Annual Review of Biochemistry, Volume 92 is June 2023. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.PMID:37068769 | DOI:10.1146/annurev-biochem-052521-033746
Source: Annual Review of Biochemistry - Category: Biochemistry Authors: Source Type: research