[Phosphatase from Proteus mirabilis].

Cell-free preparations of Proteus mirabilis contained a phosphatase (EC 3.1.3.

[Endonuclease from Proteus mirabilis].

Two isoforms of nuclease displaying DNase and RNase activities were found in the culture liquid and periplasm of Proteus mirabilis. The enzyme was isolated from the periplasm and then purified to a functionally homogeneous state. The nuclease was equally potent in cleaving denatured and native DNAs by the endonuclease mechanism and was designated Pm endonuclease.

[Biosynthesis of Proteus mirabilis nuclease].

The culture liquid and periplasm of Proteus mirabilis contained nuclease, an enzyme with DNase and RNase activities. The nuclease was most actively synthesized in the early exponential and stationary growth phases. Nuclease synthesis was regulated by nucleic acids (induction by substrate) and inorganic phosphate (end-product inhibition).

[Affinity chromatography for purification of phospholipase A2 from the venom of Central Asian cobra].

A method of affinity chromatography was developed for purification of phospholipase A2(PL-A2) from the Central Asian cobra venon. The enzyme was covalently coupled to a polyamide sorbent with phosphatidilethanolamine (PEA) and cytotoxin (CT). The effect of CA2+ concentration and the ion strength of the solution on the enzyme adsorption was studied.

[Immobilization of phospholipase A2 from Central Asian cobra venom on polyamide sorbents].

The effect of the immobilization technique and the ligand nature on catalytic properties of phospholipase A2 from the cobra venom was studied. Preparations of phospholipase A2 adsorbed on and covalently bound to polyamide sorbents were obtained. The enzyme was coupled to polyamide beads modified with glutaraldehyde.

Structural changes of liposome phospholipid packing induced by cytotoxin of the Central Asia cobra venom.

Liposomes and proteoliposomes obtained from rat brain were used; structural changes induced by Vc5 cytotoxin (CT) from Central Asia cobra venom have been studied by the EPR method using spin probes (5-, 10-, or 12-doxylstearic acid). The addition of CT to liposome samples, containing spin probes resulted in the appearance of a new EPR signal in the initial spectrum (samples without CT), typical of probes with strongly retarded mobility. The presence of hydrophobic interaction between the CT molecules and spin labelled fat acids permits the assumption that CT molecules in liposomes trap both lipid probes and phospholipids localized in the reach of action of hydrophobic forces.