Journal
CHEMISTRY & BIOLOGY
Volume 19, Issue 7, Pages 855-865Publisher
CELL PRESS
DOI: 10.1016/j.chembiol.2012.05.016
Keywords
-
Categories
Funding
- Boston Foundation
- National Institutes of Health [GM 20011]
- Howard Hughes Medical Institute
- National Center for Research Resources at the National Institutes of Health [RR-15301]
- U.S. DOE [DE-AC02-06CH11357]
Ask authors/readers for more resources
The indolocarbazole biosynthetic enzymes StaC, InkE, RebC, and AtmC mediate the degree of oxidation of chromopyrrolic acid on route to the natural products staurosporine, K252a, rebeccamycin, and AT2433-A1, respectively. Here, we show that StaC and InkE, which mediate a net 4-electron oxidation, bind FAD with a micromolar K-d, whereas RebC and AtmC, which mediate a net 8-electron oxidation, bind FAD with a nanomolar K-d while displaying the same FAD redox properties. We further create RebC-10x, a RebC protein with ten StaC-like amino acid substitutions outside of previously characterized FAD-binding motifs and the complementary StaC-10x. We find that these mutations mediate both FAD affinity and product specificity, with RebC-10x displaying higher StaC activity than StaC itself. X-ray structures of this StaC catalyst identify the substrate of StaC as 7-carboxy-K252c and suggest a unique mechanism for this FAD-dependent enzyme.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available