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J Sugatani

Publications and source records attributed to J Sugatani.

44 records · Page 3Linked to original sources
PubMed1986

[Phospholipase B].

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Electrophoresis, Polyacrylamide Gel↗
PubMed1982

Analysis of molecular species of phospholipids by field desorption mass spectrometry.

Various glycerophospholipids including their trimethylsilyl and t-butyldimethylsilyl derivatives and cerebroside were analysed by field desorption mass spectrometry with a silicon emitter. Choline glycerophospholipids with diacyl residues and also alk-1'-enyl and acyl residues gave the readily interpretable field desorption mass spectra in which a sodium cluster ion [M+NA]+ was a base peak. As to phosphatidylethanolamine and cerebroside, a protonated molecular ion [M+H+]+ was a base peak. The TMS and TBDMS derivatives gave a molecular ion [M]+. The field desorption analysis of natural phospholipids from myelin was carried out in comparison with the gas chromatographic mass spectrometric analysis.

Animals↗
PubMed1979

In vitro actions of some antibiotics on phospholipases.

The effects of some antibiotics on activities of phospholipase A2, B and C were investigated in vitro. Tetracyclines, macrolides, chloramphenicol and carbenicillin inhibited the activity of Crotalus adamanteus phospholipase A2 towards phospholipids of egg-yolk emulsions. When the ability to inhibit the activity of Penicillium notatum phospholipase B towards mixed micelles of phosphatidylcholine and Triton X-100 was investigated, polymyxin B was found to be inhibitory while chloramphenicol and carbenicillin were found to stimulate the activity of the phospholipase. The activity of Bacillus cereus phospholipase C towards the mixed micelles was inhibited by bleomycin, oleandomycin and chloramphenicol.

Carbenicillin↗
PubMed1978

Studies on a phospholipase B from Penicillium notatum. Substrate specificity.

1. The action of a highly purified phospholipase B from Penicillium notatum on 1-O-alk-1'-enyl-2-acyl-, 1-O-alkyl-2-acyl-, 1,2-diacyl-, 1-acyl- and 2-acyl-sn-glycero-3-phosphocholine, monoacyl-, diacyl- and triacylglycerols, cholesteryl oleate and p-nitrophenyl acetate was studied. 2. The hydrolysis products of the monoethermonoacylglycerophospholipids were identified as fatty acids, 1-O-alk-1'-enyl-sn-glycero-3-phosphocholine and 1-O-alkyl-sn-glycero-3-phosphocholine. The hydrolysis rates were in the following order: 1,2-diacyl-sn-glycero-3-phosphocholine greater than 1-O-alk-1'-enyl-2-acyl-sn-glycero-3-phosphocholine greater than 1-O-alkyl-2-acyl-sn-glycero-3-phosphocholine. 3. 1-Acyl-sn-glycero-3-phosphocholine was hydrolyzed about 15 times faster than 2-acyl-sn-glycero-3-phosphocholine. 4. Monoacylglycerols were hydrolyzed at the optimal pH 4.0, but diacyl- and triacylglycerols were not hydrolyzed at various pH values between 4.0 and 9.0. 5. Cholesteryl oleate and p-nitrophenyl acetate were not hydrolyzed.

Acetates↗
PubMed1975

Studies on a phospholipase B from Penicillium notatum. Purification, properties, and mode of action.

1. Phospholipase B which hydrolyzes both the acyl ester bonds of diacylphospholipids (diacyl-hydrolase) and the acyl ester bond of monoacylphospholipids or lysophospholipids, [monoacyl-hydrolase or lysophospholipase, EC 3.1.1.5] was purified from Penicillium notatum about 2000-fold over the crude extract. The final preparation was homogeneous on disc electrophoresis. The apparent molecular weight, determined by gel filtration on Sephadex G-200, was about 116,000. The isoelectric point was pH 4.0. 2. The purified enzyme was a glycoprotein. The carbohydrate content was approximately 30%, consisting of mannose, glucose, and glucosamine. The amino acid composition was also determined. 3. The ratio of monoacyl-hydrolase to diacyl-hydrolase activities was influenced by the physical state of the substrate in the assay system. It was about 1 : 1 or 100 : 1 in the presence of absence of Triton X-100, respectively, and the latter value remained constant throughout the purification procedures. 4. Both enzyme activities had the same pH optimum, 4.0, and were heat-labile. None of the metals tested had any effect on either activity except for Fe2+ and Fe3+. Diisopropyl fluorophosphate at relatively high concentrations completely inhibited both enzyme activities. 5. The Michaelis-Menten constants (Km) of the enzyme for egg lecithin were about 1.5 and 25 mM in the absence and presence of Triton X-100, respectively. The Km value for dicaproyllecithin was 9.8 mM in the absence of Triton X-100. 6. Using a mixture of 1-[14C]stearoyl-lecithin and 2-[14C]oleoyl-lecithin in the presence of Triton X-100 as a substrate, it was found that the P. notatum phospholipase B attacked the acyl ester bonds sequentially, first the 2-acyl and then 1-acyl groups.

Amino Acids↗