[Stimulating effect of human chorionic gonadotropin on the activity of guanidinoacetate-N-methyltransferase of rat testes: role of cyclic AMP].

A study was made of the influence of human chorionic gonadotropin (HCGT) on the activity of guanidineacetate-N-methyltranspherase in human testes. Guanidineacetate-methyltranspherase proved to be stimulated in the testes of the sexually immature rats in vivo under the action of HCGT on the 19th day after birth and from the 24th to the 27th day after birth. The activity of the enzyme was also increased in adult rats weighing 35--40 g.

[Regulation of L-asparaginase biosynthesis in mutants of Bacillus mesentericus 43A, poorly growing in the presence of aspartic acid].

Biosynthesis of L-asparaginase (EC 3.5.1.

[The stimulating effect of cyclic AMP, glucagon and insulin on guanidine acetate-N-methyltransferase activity in rat liver and pancreas].

N6,O2'-dibutyrylcyclo-3',5'-AMP injected to intact rats alone or in combination with theophylline increases the activity of guanidine acetate methyltransferase (GAMT) in liver and pancreas. Cyclic 3',5'-AMP and its dibutyryl analog administered immediately or two hours after the suturing of common bile duct (SCBD) stimulate the increase of pancreatic GAMT activity 2-3 fold. Glucagon, injected intraabdominally simultaneously with SCBD and administration of theophylline, dramatically increases the theophylline effect on the GAMT activity.

[Study of the structure of the histidine decarboxylase of Micrococcus sp. n. by the method of circular dichroism].

Ring dichroism spectra (RD) of histidine decarboxylase (HDC) from Micrococcus sp. n. at the regions of peptide bonds (200-240 nm) and aromatic amino acids (250-300 nm) absorption are studied.

[Isolation, purification and properties of a carboxypeptidase inhibitor from human blood serum].

Partially purified low molecular component, which inhibited the carboxypeptidase N activity in samples with hippuryl-L-lysine and bradikinine as substrates, was isolated from human blood serum by means of chromatography on DEAE-Sephadex, ultrafiltration of the fractions obtained through Amicon membranes UM-10 or UM-2 and subsequent gel filtration through Sephadex G-10. The probable molecular weight of the inhibitor was 2000. The inhibitor was thermolabile; its inhibitory activity was decreased by 50% after 30 min boiling in 0.