o-Succinylbenzoyl-CoA (OSB-CoA) synthetase (MenE) is an essential enzyme in bacterial vitamin K biosynthesis and an important target in the development of new antibiotics. It is a member of the adenylating enzymes (ANL) family, which reconfigure their active site in two different active conformations, one for the adenylation half-reaction and the other for a thioesterification half-reaction, in a domain-alternation catalytic mechanism. Although several aspects of the adenylating mechanism in MenE have recently been uncovered, its thioesterification conformation remains elusive. Here, using a catalytically competent Bacillus subtilis mutant protein complexed with an OSB-CoA analog, we determined MenE high-resolution structures to 1.76 and 1.90 Å resolution in a thioester-forming conformation. By comparison with the adenylation conformation, we found that MenE C-domain rotates around the Ser384 hinge by 139.5° during domain-alternation catalysis. The structures also revealed a thioesterfication active site specifically conserved among MenE orthologues and a substrate-binding mode distinct from those of many other acyl/aryl-CoA synthetases. Of note, using site-directed mutagenesis, we identified several residues that specifically contribute to the thioesterification half-reaction without affecting the adenylation half-reaction. Moreover, we observed a substantial movement of the activated succinyl group in the thioesterification half- reaction. These findings provide new insights into the domain-alternation catalysis of a bacterial enzyme essential for vitamin K biosynthesis and of its adenylating homologues in the ANL enzyme family.
from #AlexandrosSfakianakis via Alexandros G.Sfakianakis on Inoreader http://ift.tt/2rmpyN2
via IFTTT
Εγγραφή σε:
Σχόλια ανάρτησης (Atom)
Δημοφιλείς αναρτήσεις
-
Publication date: Available online 4 January 2018 Source: European Journal of Radiology Author(s): Peiyao Zhang, Jing Wang, Qin Xu, Zhen...
-
Abstract Purpose Overcoming the flaws of current data management conditions in head and neck oncology could enable integrated informatio...
-
Background Hyperthyroidism is associated with increased thrombotic risk. As contact system activation through formation of neutrophil extrac...
-
Publication date: Available online 6 January 2018 Source: Current Problems in Diagnostic Radiology Author(s): Mark D. Kovacs, Maximilian...
-
Background Chronic rhinosinusitis (CRS) is a commonly observed sequela after radiation therapy to the paranasal sinuses. The histopatholo...
-
Abstract Purpose Currently, intraoperative ultrasound in brain tumor surgery is a rapidly propagating option in imaging technology. We e...
-
Publication date: Available online 6 November 2017 Source: Academic Radiology Author(s): Steven J. Esses, Samir S. Taneja, Andrew B. Ros...
-
Publication date: Available online 4 November 2017 Source: Current Problems in Diagnostic Radiology Author(s): Elisabeth R. Garwood, Gre...
-
To evaluate the effect of Recurrence Score® results (RS; Oncotype DX® multigene assay ODX) on treatment recommendations by Swiss multidiscip...
Δεν υπάρχουν σχόλια:
Δημοσίευση σχολίου