Takichi Kaneko

Determination of the nucleotide composition of a deoxyribonucleic acid by high-performance liquid chromatography of its enzymatic hydrlysate: a review

Abstract The guanine-plus-cytosine content of DNA is one of the most important criteria for classification of microorganisms. Usually the G + C content is estimated by the melting temperature of the DNA. Although a number of high-performance liquid chromatography system for analyzing nucleic acid derivatives are known, their application for the G + C assay has not been widely utilized. This review covers recent work in which DNA is digested by purified enzyme(s) to form nucleotides or nucleosides, which are analyzed by HPLC. The new methods are practical and sufficiently reliable for the determination of DNA based composition.

Characterization of Strains of Pseudomonas maltophilia Which Do Not Require Methionine

Nine strains of Pseudomonas maltophilia which do not require methionine are described. Methionine-requiring and -nonrequiring strains of P. maltophilia belong to different biovars, which are designated I and II, respectively; they differ from each other with respect to phenotypic characteristics, cellular fatty acid composition, deoxyribonucleic acid base composition, and deoxyribonucleic acid-deoxyribonucleic acid hybridization. The relationship of P. maltophilia to Xan-thomonas species is also discussed.

Deoxyribonucleic Acid Homologies Among Coryneform Bacteria

The deoxyribonucleic acid homologies among 33 strains of coryneform bacteria with various cell wall types reflected the previous grouping of these organisms by Yamada and Komagata on the bases of the mode of cell division, principal amino acids in the cell wall, and the base composition of deoxyribonucleic acid. In addition, the following four homology clusters were found: (i) six strains of corynebacteria with a glycolyl type of cell wall, (ii) four strains of glutamic acid-producing bacteria, (iii) two strains of Brevibacterium linens, and (iv) three strains of coryneform bacteria containing LL-diaminopimelic acid in the cell wall.