Acyl-carrier protein-phosphopantetheinyltransferase partnerships in fungal fatty acid synthases.
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ABSTRACT:
SUBMITTER: Crawford JM
PROVIDER: S-EPMC3189688 | biostudies-literature | 2008 Jul
REPOSITORIES: biostudies-literature
Publications
Acyl-carrier protein-phosphopantetheinyltransferase partnerships in fungal fatty acid synthases.
Crawford Jason M JM Vagstad Anna L AL Ehrlich Kenneth C KC Udwary Daniel W DW Townsend Craig A CA
Chembiochem : a European journal of chemical biology 20080701 10
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Project description:The acyl carrier protein (ACP) domain shuttles substrates and reaction intermediates in type I fungal fatty acid synthases via transient protein-protein interactions. Here, using electron cryo-microscopy (cryoEM), we report the structure of a fungal FAS stalled at the dehydration reaction, which precedes the final enoyl reduction in the fatty acid biosynthesis cycle. This conformation revealed multiple contact sites between ACP and the dehydratase (DH) and enoyl reductase (ER) domains that occluded the ACP binding to the adjacent ER domain. Our data suggests a minimal path from the DH to the ER reaction site that requires minute changes in the coordinates of the structured N- and C- termini of the ACP domain.
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