Tetsuo Tobita

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The N-linked oligosaccharides, released by hydrazinolysis from the major 55-kDa family, PZP3, of porcine zona pellucida glycoproteins, were separated into neutral (28%) and acidic (72%) carbohydrate chains by anion-exchange HPLC. By competition assay, it was shown that the mixture of neutral chains has the sperm-receptor activity, while that of the acidic(More)
Hydrolysis of spinach-leaf cell walls with Driselase (a fungal enzyme preparation) released two arabino-oligosaccharides and one galactobiose, each carrying a ferulic acid moiety. The oligosaccharides were characterized by NMR spectroscopy, methylation analysis, and FABMS. They were O-(2-O-trans-feruloyl-alpha-L-arabinofuranosyl)-(1-->5)-L-arabinof uranose,(More)
The glycoproteins of porcine zonae pellucidae have been fractionated into three families (PZP1-3) by gel filtration HPLC [Nakano et al. (1987) Biochem. Int. 14, 417-423]. However, they still comprise heterogeneous molecular species differing in electric charge. We found that sulfate, but not phosphate, is contained in PZP1-3 by a simple and rapid method for(More)
The DNA binding properties of boar transition protein 1 and 3 (TP1 and TP3) were studied by means of physicochemical techniques. The ultraviolet difference absorption spectra upon TP1 and TP3 binding to rat liver nucleosome core DNA (double-stranded DNA) showed TP1- and TP3-induced hyperchromicity at 260 nm, which is suggestive of local melting of DNA. CD(More)
Several hundred fertilized pig eggs were prepared by an in vitro fertilization (IVF) technique in which follicular phase ovarian eggs were matured in vitro to metaphase II before incubation with capacitated epididymal spermatozoa for 12 h at 39 degrees C. Parthenogenetic eggs were also prepared by stimulation of the mature eggs with an electric pulse. The(More)
Four active forms of chymotrypsin C (C1, C2A, C2B, and C3) were isolated from the autolyzed porcine pancreas glands. Their molecular weights were estimated by SDS-polyacrylamide gel electrophoresis to be 29 100 for C1, 26 300 for C2A and C3, and 25 500 for C2B. The kinetic analyses of esterase activity of the enzymes toward Ac-LLeu-OEt and Ac-LPhe-OEt(More)
1. Sperm nuclei were isolated and purified from boar semen by a procedure involving differential solubilization of sperm tail and acellular materials by brief exposure to reducing reagent in the presence of cationic detergent, and sedimentation through 60% sucrose. The weight ratio of DNA:RNA: total protein: protamine in this preparation was 1.00: 0.02:(More)