Partial Reassociation Between the Deoxyribonucleic Acids of Neisseria lactamicus and Neisseria meningitidis

Abstract

The similarity in polynucleotide sequence of seven strains of Neisseria lactamicus to N. meningitidis and to each other was investigated. The per cent reassociation between single-stranded N. lactamicus deoxyribonucleic acid (DNA), immobilized on membrane filters, with labeled single-stranded DNA fragments derived from strain SD-6 (group C) of N. meningitidis varied from 75 to 56. With strain ATCC 23972 of N. lactamicus furnishing the labeled DNA fragments, reassociation was 72% with N. meningitidis, 31% with N. subflava, and 98 to 72%, with the other strains of N. lactamicus. It is concluded that on the basis of DNA reassociation N. lactamicus can be distinguished from N. meningitidis and N. subflava, but constitutes a relatively heterogeneous species. Kingsbury (5) tested 11 strains of Neisseria meningitidis for similarity in polynucleotide sequence by the deoxyribonucleic acid (DNA) reassociation technique. Ten of these strains were indistinguishable from each other by this method, suggesting that the considerable variation among them in serological specificity, represented by groups A, B, C, D, X, Y, and 29E, was reflected in small differences in the genome. Only a group Z

Effect of Glutamate on Exogenous Citrate Catabolism of Neisseria meningitidis and of Other Species of Neisseria

“…On the other hand, glutamate-stimulated citrate metabolism, in this study, proved to be a characteristic shared by a large number of strains of N. meningitidis, but only by an occasional other Neisseria. Of particular interest is the difference between strains of N. meningitidis and N. lactamicus which have been recently separated on the basis of several phenotypic characteristics (5,6) and DNA reassociation (15).…”