Sedoheptulose 7-phosphate cyclases (SH7PCs) encompass three enzymes involved in producing the core cyclitol structures of pseudoglycosides and similar bioactive natural products. One such enzyme is ValA from Streptomyces hygroscopicus subsp. jinggangensis 5008 which makes 2-epi-5-epi-valiolone as part of the biosynthesis of the agricultural antifungal agent validamycin A. We present, as...
Full Text:
-Phosphate Cyclase: ValA from Streptomyces
hygroscopicus
Kelsey M. Kean1, Sara J. Codding1, Shumpei
Sedoheptulose 7-phosphate cyclases (SH7PCs) encompass three enzymes involved in producing the core cyclitol structures of pseudoglycosides and similar bioactive natural products. One such enzyme is ValA from Streptomyces hygroscopicus subsp. jinggangensis 5008 which makes 2-epi-5-epi-valiolone as part of the biosynthesis of the agricultural antifungal agent validamycin A. We present, as...
Full Text:
from
Streptomyces hygroscopicus
Kean, K. M., Codding, S. J., Asamizu, S., Mahmud, T., & Karplus, P. A
Sedoheptulose 7-phosphate cyclases (SH7PCs) encompass three enzymes involved in producing the core cyclitol structures of pseudoglycosides and similar bioactive natural products. One such enzyme is ValA from Streptomyces hygroscopicus subsp. jinggangensis 5008 which makes 2-epi-5-epi-valiolone as part of the biosynthesis of the agricultural antifungal agent validamycin A. We present, as...
The pseudo-glycosyltransferase VldE catalyzes non-glycosidic C-N coupling between an unsaturated cyclitol and a saturated aminocyclitol with the conservation of the stereochemical configuration of the substrates to form validoxylamine A 7'-phosphate, the biosynthetic precursor of the antibiotic validamycin A. To study the molecular basis of its mechanism, the three-dimensional structures of...
Ultraviolet-protective compounds, such as mycosporine-like amino acids (MAAs) and related gadusols produced by some bacteria, fungi, algae, and marine invertebrates, are critical for the survival of reef-building corals and other marine organisms exposed to high-solar irradiance. These compounds have also been found in marine fish, where their accumulation is thought...
This thesis describes an investigation of the molecular basis of the substrate specificity and catalytic mechanism of a unique pseudoglycosyltransferase (PsGT) enzyme, VldE. PsGTs are a newly discovered group of glycosyltransferase (GT)-like proteins that catalyze the transfer of a pseudosugar to an acceptor molecule via a C-N bond formation. This...
Sugar phosphate cyclases (SPCs) are enzymes involved in the biosynthesis of many important natural products. SPCs form a unique cyclitol during the early steps in the biosynthesis of many natural products. These natural products include rifamycin, which is chemically modified to rifampicin and used clinically as an antituberculosis drug, and...
The function of a protein is defined by its three-dimensional structure, and in understanding the three-dimensional structure of a protein, we gain an understanding of its function and mechanism. Protein structures, especially at high resolution, can provide detailed insights into many elements of enzyme function and catalysis – identifying residues...