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V M Lipkin

Publications and source records attributed to V M Lipkin.

At least 91 records · Page 5Linked to original sources
PubMed1990

[Cyclic GMP phosphodiesterase from bovine retina. Amino acid sequence of beta-subunit and nucleotide sequence of corresponding cDNA].

Primary structure of beta-subunit of the cyclic GMP phosphodiesterase has been determined by the parallel analysis of the protein amino acid sequence and the corresponding cDNA nucleotide sequence. The beta-subunit contains 852 amino acid residues, its molecular mass is 98291 Da. A significant homology is found between beta- and alpha-subunit of the cGMP phosphodiesterase.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed1989

Calmodulin-independent bovine brain adenylate cyclase. Amino acid sequence and nucleotide sequence of the corresponding cDNA.

An individual catalytic component of calmodulin-independent adenylate cyclase has been isolated from bovine brain cortex. Affinity chromatography on an immunosorbent was used. The amino acid sequence of adenylate cyclase as well as the corresponding nucleotide sequence of the cDNA has been determined. cDNA of adenylate cyclase encodes a protein consisting of 834 amino acid residues and the signal peptide (19 amino acid residues). A series of adenylate cyclase isoforms has been found. A homology between adenylate cyclases from bovine brain, E. coli and Bordetella pertussis has been revealed.

Adenylyl Cyclases↗
PubMed1989

[Catalytic component of calmodulin-independent adenylate cyclase from bovine brain. Isolation and determination of partial amino acid sequence].

The catalytic component of calmodulin-independent adenylate cyclase of cattle cerebral cortex was solubilized and purified to the homogeneous state. The conditions for preparative obtaining of the enzyme on the column with immobilized antibodies to adenylate cyclase were found. These antibodies were proved to interact with the calmodulin-independent rather than the calmodulin-dependent form of the enzyme. Molecular mass of the calmodulin-independent adenylate cyclase determined electrophoretically is 140 +/- 10 kDa. Amino acid composition of the enzyme and sequences of its fragments (in total 300 amino acid residues) obtained upon treatment with lysyl-specific proteinase from Achromobacter liticus were determined. Clone containing a cDNA 605 bp insertion coding for the 183 amino acid residue fragment of adenylate cyclase was isolated from the bovine brain cDNA library. Homology of this fragment to the known sequences of Escherichia coli and Bordetella pertussis adenylate cyclases was revealed.

Adenylyl Cyclases↗
PubMed1988

Active sites of the cyclic GMP phosphodiesterase gamma-subunit of retinal rod outer segments.

Monoclonal antibodies were prepared to the gamma-subunit of the cGMP phosphodiesterase. One of them gamma p-1, suppresses the activation of phosphodiesterase through the alpha-subunit of transducin. The gamma-subunit fragment 24-45 rich in Arg and Lys residues is involved in gamma p-1 binding and is essential for the gamma-subunit interaction with transducin. Carboxypeptidase Y cleaves off seven amino acid residues from the C-terminus of the gamma-subunit resulting in phosphodiesterase activation. Thus, the C-terminal fragment of gamma-subunit participates in phosphodiesterase inhibition.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed1987

Primary structure of bovine cerebellum GTP-binding protein G39 and its effect on the adenylate cyclase system.

The primary structure of bovine cerebellum GTP-binding protein alpha-subunit, protein G39, was determined by parallel analysis of the protein amino acid sequence and the corresponding cDNA nucleotide sequence. The protein consists of 354 amino acid residues and has a molecular mass of 40064 Da. High homology between G39 and other G-proteins, especially rat brain G0, was shown. An assumption is made that certain brain adenylate cyclase system properties are determined by the presence of G39.

Adenylyl Cyclases↗
PubMed1987

Cyclic GMP phosphodiesterase from bovine retina. Amino acid sequence of the alpha-subunit and nucleotide sequence of the corresponding cDNA.

The alpha-subunit primary structure of cyclic GMP phosphodiesterase has been determined by parallel analysis of the protein amino acid sequence and the corresponding cDNA nucleotide sequence. The enzyme alpha-subunit contains 858 amino acid residues, its N-terminal amino group being acetylated. The partial primary structure of the enzyme beta-subunit has also been elucidated. A significant homology has been found between the alpha- and beta-subunits of cGMP phosphodiesterase.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed1986

[Preparation and characteristics of monoclonal antibodies against GTP-binding protein from the bovine retina].

Five monoclonal antibodies against the native GTP-binding protein (transducin) from bovine retina have been prepared. By immunoblotting and immunoenzymatic analysis of the isolated alpha- and gamma-subunits of transducin and the beta gamma-subunit complex it was determined that two monoclonal antibodies A3G7 and A3C10 recognize linear antigenic determinants on the alpha-subunit, two other, A3E4 and 3B3, bound specifically to the gamma-subunit, and monoclonal antibodies 1C3 interact only with native transducin. Both antibodies against the alpha-subunit inhibited transducin GTPase activity, whereas antibodies A3E4, 3B3 and 1C3 did not affect it.

Animals↗
PubMed1985

[The role of sulfhydryl groups in the functioning of DNA-dependent RNA-polymerase].

Sulfhydryl groups of Escherichia coli DNA-dependent RNA polymerase were chemically modified with alkylating and mercuric-containing compounds. Iodoacetic acid and iodoacetamide were shown not to affect the enzymatic activity, whereas N-ethylmaleimide and mercuric-containing compounds completely inhibit the RNA synthesis. RNA polymerase modified with mercuric ions looses the ability of binding with promoter--containing DNA fragments. Moreover, mercuric ions inhibit the RNA elongation stage. Suggestion is made the Cys residues of RNA polymerase play a key role in double-stranded DNA unwinding. It is shown that SH-groups of beta- and beta'-subunits participate in the binding with double-stranded fragments of DNA.

Chemical Phenomena↗
PubMed1985

[Isolation and characteristics of cyanogen bromide peptides of transducin alpha and beta subunits].

The alpha- and beta-subunits of the GTP-binding protein (transducin) from cattle retina were cleaved with cyanogen bromide. 21 peptides covering 90-100% of the amino acid sequence of the alpha- and beta-subunits were isolated from the hydrolyzate. Cyanogen bromide peptides complete or partial amino acid sequence was determined, the results were compared with those by Numa and coworkers [1] and Lochrie et al. [2] at the primary structure of the transducin alpha-subunit deduced from the nucleotide sequence of the cDNA. The structure by Lochrie is shown to differ much from the true structure of the alpha-subunit; probably, the investigators isolated cDNA, corresponding to the gene for some GTP-binding protein homologous to transducin, but not to the gene for the transducin alpha-subunit. The Numa's structure also contains an error. The final primary structure of the transducin alpha-subunit is given. The protein polypeptide chain consists of 349 amino acid residues and has an acetylmethionine residue as the N-terminal residue.

Amino Acid Sequence↗
PubMed1985

[Topography of cysteine residues in DNA-dependent RNA-polymerase].

Chemical modification of DNA-dependent RNA polymerase with monoiod-[14C]acetic acid and N-[14C]ethylmaleimide has been carried out and position of superficial and functionally important as well as enzymatically non-significant, exposed cysteine residues have been localised in the enzyme. Topography of cysteine residues in the RNA-polymerase alpha-subunit is thoroughly studied. The results are summarized in a model.

Amino Acid Sequence↗