共查询到20条相似文献,搜索用时 31 毫秒
1.
2.
3.
H Tschesche R Klauser D Cechová V Jonáková 《Hoppe-Seyler's Zeitschrift für physiologische Chemie》1975,356(11):1759-1764
The trypsin inhibitor from bovine colostrum has been separated into several forms by CM-Sephadex and DEAE-cellulose chromatography. These forms differ in the amount and composition of the carbohydrate they contain, which has been quantitated for four components by gas-liquid chromatography and standrad colorimetric procedures. The monosaccharides fucose, mannose, galactose, galactosamine, glucosamine and sialic acids have been determined. A microheterogeneity was establish ed in the carbohydrate moiety, which amounts to about 40% of the total molecular weight (Mr 11 000 - 14 000) of bovine colostrum inhibitor. 相似文献
4.
5.
6.
7.
8.
9.
Several methods were employed for the preparation of salt-free trypsin samples which were used to determine the electrometric titration curves of the enzyme. These curves point to a maximum acid-binding capacity below pH 2. Stoichiometric analysis indicates the presence of 6 carboxyl groups per 10,000 g. of proteins, 1 imidazole group, and 13 hydroxyl-binding groups. Calcium has a specific effect on the titration curves by increasing the acidity of the carboxyl groups in the pH range 3.5 – 5. This effect is not shown by potassium, sodium, or even the bivalent magnesium ion. It is attributed to the formation of a specific complex between the enzyme and the calcium ions, involving the carboxyl groups of the protein. The equally specific protective effect of calcium on the self-digestion of trypsin can therefore be explained by assuming the formation of a complex which stabilizes the enzyme. 相似文献
10.
11.
12.
13.
14.
15.
M W Hunkapiller M D Forgac E H Yu J H Richards 《Biochemical and biophysical research communications》1979,87(1):25-31
NMR studies of the complex between trypsin and soybean trypsin inhibitor with 1-13C-arginine and modified inhibitor with 1-13C-lysine show that these complexes involve almost exclusively non-covalent binding of the inhibitor to the enzyme for trypsin/13C-Lys-inhibitor at pH 6.5 and 8.1 and for trypsin/13C-Arg-inhibitor at pH 5.0. At pH 7.1 for trypsin/13C-Arg-inhibitor both non-covalent and acyl enzyme forms are observed. Under no conditions did we observe evidence for a tetrahedral adduct between enzyme and inhibitor. 相似文献
16.
17.
On some autolyzed derivatives of bovine trypsin 总被引:4,自引:0,他引:4
18.
19.