Question

Please read through and answer the question below. Thank you

Module 1 Module 2 Module 3 Module 5 Release Load Module 4 Module 6 KR KR KR AT KSXAT KS XAT KS AT KS AT Elucidete andl Ruplain the order tbat modules and 5 in oseteg to y above erthronoude 5 using the cdiagram

Answer 1

Ans:;Biosynthesis of deoxyerythronolide B in the route to erythromycin A . Deoxyerythronolide B synthases (DEBS) catalyze iterative claisen-type condensations by progressively associating one propionyl-CoA primer unit with six methylmalonyl-CoA extender units. Each DEBS molecule contains two modules, these modules representing a physical location for a claisen-type condensation. Once loaded onto the ketosynthase (KS) of module 1 by the loading acyl transferase (AT) and the acyl carrier protein (ACP) domains, propionyl-CoA condenses with a methylmalonyl unit loaded onto module 1 ACP by the module 1 AT domain. After that, ketoreductases (KR), specific for each module, reduce the resulting ketone group. The chain then passes in a progressive manner from module 1 ACP (via a phosphopantetheine cofactor) to the KS domain of the next module (module 2). Following these iterative condensations, the polyketide chain grows before being released and cyclized by a thioesterase/claisen cyclase (TE). Other abbreviations: ER are enoyl reductase and DH: dehydratase.

SCOA PROPIOYL Co2 H COA EXTENDER UN I UNIT bBeL- Ac, Ke AT Ke Acp KS AT KRAtpl_r er KL Ar b.ERKP Ace1_从槤R&ATRET OH 해 Hl