Identification, genetics, and structure of cyclothiazomycin
C.
(a) MALDI-TOF MS analysis showing spectra of unreacted (black spectrum,
top) and DTT-labeled (red spectrum, bottom) extracts of WC-3908, the
producer of cyclothiazomycin C. Peaks labeled with an asterisk do
not correspond to DTT-labeled cyclothiazomycin C. (b) Conserved open-reading
frames from each of the three cyclothiazomycin gene clusters (precise
cluster boundaries are not yet established). Genes are color-coded
with proposed functions given in the legend. The strain used for the
comparison of cyclothiazomycin A is Streptomyces hygroscopicus subsp. jinggangensis 5008, and cyclothiazomycin
B is Streptomyces mobaraensis. (c) Precursor peptide
sequences of cyclothiazomycins A, B, and C. Highlighted in red are
residues that differ in the core region of the peptide. The asterisk
denotes the leader peptide cleavage site. (d) Structures of cyclothiazomycins
A, B, and C.