Genetic studies of the ribosomal proteins in Escherichia coli. 3. Compositions of ribosomal proteins in various strains of Escherichia coli

Summary The comparative chromatographic investigations into the ribosomal proteins of various strains of E. coli have demonstrated that most of the strains including three strains of E. coli subsp. communior had ribosomes with the same protein compositions (C-type). The ribosomes from strain B are different from the C-type ribosomes in having the specific 30-4 (B) component in place of 30-4 (B-type), while those from strains K 12 may be distinguished from the type-C ribosomes by the presence of the specific 30-7 (K) component in place of 30-7 (K-type) or, in addition to 30-7 (K), the presence of 30-9 (W3637) in place of 30-9 (K-3637 type). Two strains, IAM 1132 and IAM 1182, have R-type ribosomes, in which at least six 50s proteins and four 30s protein components are distinct from the corresponding protein components in the C-type ribosomes.     

Evolution of the mitochondrial genetic code IV. AAA as an asparagine codon in some animal mitochondria

Summary Differences in assignments from those in the universal genetic code occur in codes of mitochondria. In this report, the published sequences of the mitochondrial genes for COI and ND1 in a platyhelminth (Fasciola hepatica) are examined and it is concluded that AAA may be a codon for asparagine instead of lysine, whereas AAG is the sole codon for lysine in this species.     

Phylogenetic relationships in the division Lipastromorphi (Coleoptera,Carabidae) of the world as deduced from mitochondrial ND5 gene sequences

Phylogenetic trees have been constructed using mitochondrial ND5 gene sequences of 85 specimens representing 40 species belonging to the division Lipastromorphi of the subtribe Carabina (= genus Carabus s. lat.) of the world. In the trees constructed by several methods, there have been recognized a basal split into two lineages, A and B, which are further divided into 2 (A1 and A2) and 9 (B1-B9) sublineages, respectively. Each sublineage and the clustering of the species in the trees are more or less linked to their geographic distribution. Morphology of the species within A1 or A2 in the lineage A is similar, and the species in most of the sublineages in the lineage B are common in a number of important morphological characters in spite of their long evolutionary histories. Whilst such a morphological stability, considerable morphological changes may be recognized upon or after split of lineages and sublineages. Based on the molecular phylogeny together with the morphological data, the pattern of diversification is discussed.     

Genetic studies of the ribosomal proteins in Escherichia coli. I. Mutants and strains having 30s ribosomal subunit with altered protein components

Summary Two 30s ribosomal protein components, 30-4_K and 30-7_K, from E. coli K12 strain were clearly distinguished on the CMC column chromatogram from the corresponding protein components, 30-4_B and 30-7_B, from B strain. The 30-7_K component was shown to correspond to the K-character.A mutant strain of K12, W3637, had an altered 30s ribosomal protein component, 30-9_W3637.The characters of 30-4_K, 30-7_K, 30-9_W3637 and str ^r were found to be cotransduced from W3637 to B strain by Plke phage in 16 out of 20 str ^r transductants. The 30-9_W3637 and 30-4_K components were separated from str ^r in 4 str ^r transductants. These results indicate that (1) neither 30-4 nor 30-9 is the protein whose mutational change leads to str ^r, and (2) the genes specifying the 30s ribosomal proteins, 30-4, 30-7, 30-9 and str are linked on the chromosome.Abbreviations used CMC carboxymethyl cellulose - str streptomycin