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M S Odintsova

Publications and source records attributed to M S Odintsova.

At least 19 recordsLinked to original sources
PubMed2005

[Genomics and evolution of cellular organelles].

The structure, functions, and evolution of cellular organelles are reviewed. The mitochondrial genomes of eukaryotes differ considerably in size and structural organization mainly due to the length variation in noncoding regions and the presence of introns. The mitochondrial genomes of angiosperms are the largest and most complicated. Gene content in eukaryotic mitochondrial genomes is similar. They usually encode all types of rRNA, a complete or partial complement of tRNA, and a limited number of proteins essential for mitochondrial functions. In all eukaryotes studied, mitochondrial genomes code for two highly hydrophobic proteins involved in respiration, cytochrome b and subunit 1 of cytochrome oxidase. Genome structure and gene content in plastids, mainly in higher plant chloroplasts, are highly conserved. Plastid genomes of algae are more variable in gene composition and contain several unique genes absent in the chloroplast DNA of higher plants. Plastid genomes encode proteins involved in transcription and translation, as well as proteins of the photosynthetic apparatus. Both types of cellular organelles are supposed to be of endosymbiotic origin. Modern plastids originate from a cyanobacterial ancestor. Alpha-proteobacteria, especially the most mitochondrion-like rickettsia, gave rise to mitochondria. The origin of plastids of higher plants and green algae as a result of primary endosymbiosis and that of other algal lineages by secondary endosymbiosis are briefly discussed.

Animals↗
PubMed2002

[The mitochondrial genome of protists].

The data on the structure and functions of the mitochondrial genomes of protists (Protozoa and unicellular red and green algae) are reviewed. It is emphasized that mitochondrial gene structure and composition, as well as organization of mitochondrial genomes in protists are more diverse than in multicellular eukaryotes. The gene content of mitochondrial genomes of protists are closer to those of plants than animals or fungi. In the protist mitochondrial DNA, both the universal (as in higher plants) and modified (as in animals and fungi) genetic codes are used. In the overwhelming majority of cases, protist mitochondrial genomes code for the major and minor rRNA components, some tRNAs, and about 30 proteins of the respiratory chain and ribosomes. Based on comparison of the mitochondrial genomes of various protists, the origin and evolution of mitochondria are briefly discussed.

Animals↗
PubMed1999

Nucleoid proteins of pea chloroplasts: detection of a protein homologous to ribosomal protein.

Basic proteins were isolated from purified pea chloroplast nucleoids by acid extraction. Using RP-HPLC, the component composition of the basic proteins was studied. SDS-PAGE of major HPLC-fractions showed that the basic nucleoid proteins are heterogeneous with mol. masses of components from 17 to 30 kDa. One polypeptide with mol. mass of 28 kDa (P28) was obtained by RP-HPLC. The sequencing of three tryptic peptides of P28 (T6, T17, and T19) showed that they are homologous to the ribosomal protein L19 of Saccharomyces cerevisiae. The possible functional role of ribosomal proteins in chloroplast nucleoids is discussed.

Amino Acid Sequence↗
PubMed1995

Nucleoids of pea chloroplasts: microscopic and chemical characterization. Occurrence of histone-like proteins.

The chloroplast genome is highly condensed and packed into discrete structures called "nucleoids". Each pea chloroplast contains 16-20 spherical nucleoids randomly located in the matrix of organelle. Nucleoids are shown to contain DNA, RNA and proteins (1:0.62:2.3). Approximately 30 polypeptides (mol. masses 94 to 12 kD) have been found in nucleoids. Chloroplast DNA is associated with acidic as well as basic proteins, two of which are electrophoretically similar to histones H2A+H2B and H3 of pea cell nuclei. Amino acid composition of these proteins demonstrates high similarity with "HU" proteins of E. coli.

Cell Fractionation↗
PubMed1983

Ribosomal acidic proteins of eucaryotic cells. Isolation of a protein from pea seedlings equivalent to E. coli L7/L12.

By the method of ethanol-salt extraction with ion-exchange chromatography on CM-cellulose an acidic protein of pea 80S ribosomes was isolated. This protein located in the large subunit, had a molecular weight of 14 000 and an IEP of 4.7. The protein is partially phosphorylated, alanine-rich and has methionine at the N-terminal position. Based on these characteristics and on the comparative study of tryptic hydrolyzates of the plant protein and E. coli L7/L12, the protein so obtained is found to be homologous to the L7/L12 of the procaryotic ribosomes.

Amino Acids↗
PubMed1983

[Some structural properties of 80S acid protein from pea ribosomes].

The 80S acid protein from pea ribosomes similar to the L7/L12 protein from E. coli was studied. This protein was found to be rich in alanine (18 mol.%) and to contain an acid amino acids excess over basic ones, the ratio of basic amino acids to acid ones was 0.42. As in the case of other eukaryotic L7/L12 homologs studied, the N-terminal amino acid of the protein is methionine. Using the double immunodiffusion technique, no crossreaction of E. coli anti-L7/L12 with 80S acid protein from pea ribosomes was observed. It was assumed that the protein molecule contains conservative sites responsible for the specific functioning of eukaryotic L7/L12 homologs.

Amino Acids↗
PubMed1982

[Acid proteins of eukaryotic cell ribosomes. Isolation of the protein similar to E. coli L7/L12 from 80S pea ribosomes].

Using ethanol-salt extraction and ion-exchange chromatography, an acid protein was isolated from 80S pea ribosomes. The protein is localized in the large subunit, is phosphorylated and has a molecular weight of 14000 and pI of 4.7. These features and the results of a comparative study of tryptic hydrolysates of the plant protein and of the protein under study suggest that the latter is homologous to the ribosomal protein L7/L12 of a prokaryotic type.

Escherichia coli↗
PubMed1981

Genetic control of plastid differentiation. 3 ultrastructure of plastids in different green revertant spots of the plastom mutant Pl-alb1 of Lycopersicon esculentum.

Reverse mutations in plastid DNA give rise to phenotypically different green spots on the white tissues of the homoplastic plastom mutant Pl-alb1. The structure of the plastids in one yellow-green, one green and one dark-green spot, each arising by independent reverse mutation, was studied by means of electron microscopy. Although the same revertant plastid types (type 1 with a weakly developed lamellar system; type 2 with vacuolized grana, and type 3 with a wild type-like structure were found in all three spots, variations in separation of Pl-alb1 and revertant plastids, and in the predominant revertant plastid type, were observed among the spots investigated. The revertant plastids of different phenotype occurred not only within one spot, but also within one cell. An hypothesis explaining this phenomenon is suggested.

Chloroplasts↗
PubMed1979

Altered chloroplast ribosomal proteins in a yellow mutant of Chlamydomonas reinhardii.

Ribosomes and ribosomal proteins from wild-type and a yellow mutant of Chlamydomonas reinhardii were analysed and compared by two-dimensional gel electrophoresis. Mixothrophycally grown yellow-27 mutant differs from wild-type cells in lowered chlorophyll content and grana formation of the chloroplast. Analytical ultracentrifuge analyses of cell extracts show a reduced amount of free 70S ribosomes and increased level of 50S subunits in the mutant cells. Similar results were obtained by electronmicroscopical method. Two-dimensional gel electrophoresis shows alterations in protein composition of 70S ribosomes of the mutant. Two proteins of 70S ribosomes have been altered. One of them with high molecular weight is practically absent while there is an additional, intensively stained spot in the mutant. Since the mutation is inherited in a non-Mendelian manner it is possible that the protein alterations in 70S ribosome are localized in the chloroplast DNA.

Chlamydomonas↗
PubMed1979

Yellow mutations alter chloroplast ribosomal proteins in Chlamydomonas reinhardii.

Ribosomes and ribosomal proteins from wild-type and three yellow mutants of Chlamydomonas reinhardii were analyzed and compared by two-dimensional gel-electrophoresis. Mixotrophycally grown mutants differ from wild-type cells in lowered chlorophyll content. Analytical ultracentrifugation analysis of cell extracts showed a reduced amount of 70S ribosomes and an increased level of 50S subunits in mutants y-27 and y-28. Two-dimensional gel electrophoresis indicated considerable alterations in the protein composition of 70S ribosomes of the mutants. Two proteins of 70S ribosomes were altered in the y-27 and y-28 mutants. Two proteins were absent from the electrophoretograms of the yellow-76 mutant and seven proteins were present in lowered concentrations. The mutations are inherited in a non-Mendelian manner. The protein alterations in 70S ribosome are most probably localized in the chloroplast DNA.

Chlamydomonas↗
PubMed1977

[Mitochondrial ribosomes].

Some present-day conceptions on the structure and physiochemical and functional properties of mitochondrial ribosomes of higher and lower eukaryotes are reviewed. Mitochondrial ribosomes are compared to the ribosomes of prokaryotic and eukaryotic types and plastid ribosomes; biogenesis and functions of mitochondrial ribosomes are also discussed.

Animals↗
PubMed1976

[Chloroplast ribosomes].

A brief review of modern concepts on the structure and properties of chloroplast ribosomes is given. An attention is paid to the similarity of 70S chloroplast ribosomes, 80S cytoplasmic ribosomes and ribosomes of prokaryotic type which is interesting from the viewpoint of the origin and evolution of plastids. Problems of rRNA and ribosomal proteins biosynthesis, of biogenesis and functions of chloroplast ribosomes are also considered.

Chloroplasts↗
PubMed1975

On the origin of plastids.

The buoyant density in CsCl of ribosomes from chloroplasts of the green alga Chlorella pyrenoidosa and two species of higher plants, Pisum sativum and Chenopodium album, has been studied. From the relative protein content it was calculated that 70S ribosomes from chloroplasts are much smaller than 80S cytoplasmic ribosomes (3.0-3.1 X 10(6) and 4.0 X 10(6) daltons) and slightly larger than 70S ribosomes from bacteria (E. coli 2.5 X 10(6) daltons). Chloroplast ribosomes from pea seedlings were analyzed by two-dimensional polyacrylamide gel electrophoresis. They appear to contain 71 proteins. This indicates that chloroplast ribosomes contain a larger number of proteins than do the ribosomes from E. coli and other species of Enterobacteriaceae. Further study will permit a probable evaluation of the validity of Mereschkowsky's hypothesis that the photosynthetic plastids of eukaryotic plant cells are the evolutionary descendants of endosymbiotic blue-green algae.

Biological Evolution↗