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Title: The effect of divalent cations on the thermostability of type II polyketide synthase acyl carrier proteins

The successful engineering of biosynthetic pathways hinges on understanding the factors that influence acyl carrier protein (ACP) stability and function. The stability and structure of ACPs can be influenced by the presence of divalent cations, but how this relates to primary sequence remains poorly understood. As part of a course‐based undergraduate research experience, we investigated the thermostability of type II polyketide synthase (PKS) ACPs. We observed an approximate 40 °C range in the thermostability among the 14 ACPs studied, as well as an increase in stability (5–26 °C) of the ACPs in the presence of divalent cations. Distribution of charges in the helix II‐loop–helix III region was found to impact the enthalpy of denaturation. Taken together, our results reveal clues as to how the sequence of type II PKS ACPs relates to their structural stability, information that can be used to study how ACP sequence relates to function. © 2018 American Institute of Chemical EngineersAIChE J, 64: 4308–4318, 2018

 
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Award ID(s):
1652424
PAR ID:
10077237
Author(s) / Creator(s):
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Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
AIChE Journal
Volume:
64
Issue:
12
ISSN:
0001-1541
Page Range / eLocation ID:
p. 4308-4318
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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