That is, sPBP 656 (PBP 6 containing the MMD of PBP 5) exhibited a dd-CPase activity toward both substrates that was more like PBP 5 than PBP 6, but sPBP 565 PF-02341066 research buy (PBP 5 containing the MMD of PBP 6) was not active on either of two substrates. In addition to its decreased dd-CPase activity, PBP 565 also bound and hydrolyzed the β-lactam BOCILLIN FL much less well than any of the other proteins. These behavioral changes
of sPBP 565 may not have been due to the improper folding of the molecule because CD spectral analyses predict that there is no gross alteration in the composition of the overall secondary structure of sPBP 565 compared with sPBP 5, except that there is 3% less β-sheet
structure in the former. Although the reason for the altered behavior of sPBP 565 is not clear, a gross change in the microarchitecture of the active site cannot be ruled out. Because β-sheet structures are not usual components of active sites, the lower percentage of the β-sheet structure in sPBP 565 is not likely the key feature for its altered behavior. Nevertheless, the possible changes include altering the size and volume of the substrate-binding pocket that may change the affinity or the activity of the chimeric protein toward specific substrates. In any case, the ability of each PBP to act as a dd-CPase correlates exactly with its ability to complement cell shape changes in vivo, 3-deazaneplanocin A clinical trial strongly suggesting that this activity is responsible for the shape maintenance phenotype. We thank Robert A. Nicholas for providing the plasmid pT7-cPBP5 and for suggestions regarding the construction of sPBPs. We also acknowledge Rakesh Sikder for initiating the computational work. This work was supported by a grant from the Department of Science and Technology, the Government of India, to A.S.G., and K.D.Y. was supported ID-8 by a grant R01-GM061019 from the US National Institutes of Health and by the Arkansas Biosciences Institute, the
major research component of the Arkansas Tobacco Settlement Proceeds Act of 2000. Fig. S1. Structures of the peptide substrates. Please note: Wiley-Blackwell is not responsible for the content or functionality of any supporting materials supplied by the authors. Any queries (other than missing material) should be directed to the corresponding author for the article. “
“3-Methoxy-2-methyl-carbazole-1,4-quinone (1) together with carbazomycins D (2) and F (3) were isolated from the crude extract of Streptomyces CMU-JT005, an actinomycete with nematicidal activity. 3-Methoxy-2-methyl-carbazole-1,4-quinone is reported here for the first time from nature. In this paper, we describe the isolation and structure elucidation of the compounds together with the characterization of the Streptomyces strain CMU-JT005.