Cornexistint, a new compound demonstrating promising herbicidal activity, was purified from the culture nitrate of a newly-isolated fungus identified as Paecilomyces variotii SANK 21086. The compoundwas extracted with organic solvents from the culture nitrate, purified using column chromatography on Sephadex LH-20 and finally crystallized from methylene chloride. Following analysis of its physico-chemical properties it was identified to be a new compound belonging to the nonadride group. Chemical structure elucidation was conducted by analyses of various spectral data and the structure was finally confirmed by means of X-ray crystallographic analysis. Based on its herbicidal characteristics cornexistin may be classified as a postemergence herbicide active against certain young annual and perennial monocotyledonous and dicotyledonous plants with selective protection for corn.
A novel acyl-CoA : cholesterol acyltransferase (ACAT) inhibitor, designated epi-cochlioquinone A has been isolated from the fermentation broth of Stachybotrys bisbyi SANK17777. The molecular formula, physicochemical properties, NMRspectroscopic analysis and X-ray crystallographic analysis revealed that this compoundwas a stereoisomer of cochlioquinone A, which has been previously reported as a nematocidal agent. It inhibited ACATactivity in an enzyme assay using rat liver microsomes with an IC50 value of 1.7pu. However, it showed about 10-fold less potent inhibitory effect on plasma lecithin cholesterol acyltransferase (LCAT) than on ACAT. In addition, it inhibited in vivo cholesterol absorption in rats by 50% at 75mg/kg.
gional NMR Facility (Grant No. CHE-79-16324). We also thank Andrea Owyeung for the illustrations. Supplementary Material Available: Tables of positional and thermal parameters and complete interatomic distances and angles for 3-6, 8, 10, and 11 (62 pages); tables of observed and calculated structure factors (81 pages). Ordering information is given on any current masthead page. Tables of crystallographic data for the compounds 4,1 23 Tl[5]-2/3C7H8,7 Tl[6],8 98-V2C6H6,4 [(PPh3)2N][10],5 and Na[ll]6 were supplied with the now-published initial preliminary communications pertaining to these structures.
Proteolytic enzymes with gelatinolytic activity in the synovial fluid (SF) of temporomandibular joint (TMJ) arthropathies were assayed by gelatin-impregnated gel enzymography. SF samples were collected from 10 TMJs in patients with closed lock (CL) condition and 5 TMJs from asymptomatic healthy volunteers. Two proteinases with gelatinolytic activities at 92 kDa and 72 kDa were detected in both the normal and the diseased TMJs. Also detected were weak bands at molecular weights of 83 kDa and 66 kDa. All of these proteinase activities were inhibited by EDTA and tissue inhibitor of metalloproteinases (TIMP), required Ca2+ for activation, and were detected with gelatin but not casein as substrate, suggesting that these enzymes were matrix metalloproteinases (MMPs). The 72 kDa and 66 kDa bands further reacted with anti-MMP-2 antibody by Western blot analysis, and the proteinases in the TMJ-SF could cleave type IV collagen in vitro without any activation. These four activities identified by enzymography were, therefore, identified as 92 kDa-gelatinase (proMMP-9), 83 kDa-gelatinase (active MMP-9), 72 kDa-gelatinase (proMMP-2) and 66 kDa-gelatinase (active MMP-2). Densitometric analyses of these bands revealed higher levels of the active form of MMP-9 in the CL patients compared to controls. These findings suggest that MMP-2 and -9 could be dominant proteinases in the TMJ-SF and possibly reflect TMJ pathology.
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