Gas-chromatographic screening of capsular polysaccharides of Neisseria meningitidis.

Thirteen systemic strains, i e strains isolated from systemic infections, and 77 carrier isolates of Neisseria meningitidis were serogrouped by agglutination and analyzed by gas chromatography (GC) of phenol extracts. For systemic strains the sugar patterns were in accordance with their group-specific capsular polysaccharides (CPS). Some carrier isolates revealed unexpected GC profiles. Upon immunological retesting with new sera, GC results were generally confirmed. Occasional isolates initially serogrouped as B or Y completely lacked neuraminic acid. Some non-groupable isolates were shown by ultracentrifugation and GC to have significant amounts of this sugar likely to originate from CPS of known composition or from unknown polysaccharides. One such originally non-groupable isolate showed a weak agglutination reaction specifically with group B antiserum when reexamined. Generally, carrier isolates had lower amounts of CPS than systemic strains of the same group. Five successive isolates from one carrier were first serogrouped as X, Z or non-groupable, but they had high amounts of galactosamine and 2-keto-3-deoxy octonate, sugars characterizing CPS of serogroup 29E. These isolates were confirmed by agglutination with recently available group 29E antiserum to be of this serogroup, which has not been reported before in Norway. Ultracentrifugation revealed the presence of unknown polysaccharides containing glucose, galactose or glucosamine, but further purification of these polymers is required to determine their composition and immunological importance.

Patterns of extracellular proline-specific endopeptidases in Legionella and Flavobacterium spp. demonstrated by use of chromogenic peptides.

Some Legionella strains possess a strong extracellular proline-specific endopeptidase (PSE) activity. Using an enlarged selection of chromogenic peptides representing a variety of N-terminal amino-acids binding to a -prolyl-proline, paranitroanilide chain, PSE activity of Legionella and Flavobacterium strains was examined. Differences in PSE activity emphasized the importance of the chemical structure at the nonchromogenic end of the peptide substrates. There seem to be distinct patterns of N-terminal specificity of PSE in the two bacterial groups.

Oxidase positive rods from cases of suspected gonorrhoea. A comparison of conventional, gas chromatographic and genetic methods of identification.

Genito-urethral specimens from 3260 women and 1170 men, with ailments suggestive of gonorrhoea, were examined for growth of oxidase positive rodshaped bacteria, as well as of gonococci. Moraxella osloensis was identified in 26 cases (0.64 per cent of women and 0.43 per cent of men). Three patients harboured phenylalanine negative (or weakly reacting) and tryptophan deaminase negative M. phenylpyrouvica and, in three cases, a Flavobacterium species was detected. Among six oropharyngeal specimens from patients suspected of gonorrhoea, two yielded growth of oxidase positive rods, Kingella kingae and Neisseria elongata, respectively, N. gonorrhoeae was isolated from 537 patients, i.e., 12.1 per cent of all cases. The isolates of oxidase positive rods were in most cases completely identified by streptomycin resistance transformation. On this basis, the diagnostic reliability of some morphological and cultural-biochemical tests and gas chromatography was examined. Gas chromatographic analysis of fatty acid and alcohol composition of whole cells proved distinctive of species defined genetically, irrespective of confusing behaviour of some strains in other tests.

Gas chromatography of bacterial whole cell methanolysates. VII. Fatty acid composition of Acinetobacter in relation to the taxonomy of Neisseriaceae.

The cellular fatty acids of seventeen Acinetobacter strains were determined. Most acids identified were previously found in neisseriae and moraxellae. Specific for Acinetobacter was 2-hydroxydodecanoid acid and a few minor unidentified components. The fatty acid data were analysed by numerical methods and compared with previous results obtained for neisseriae and moraxellae. The findings were consistent with genetic evidence for some affinities of genus Acinetobacter to genus Moraxella and "false neisseriae". Occasionally, a high resemblance in fatty acid pattern was demonstrated between a Moraxella strain and certain strains of Acinetobacter, and also between an Acinetobacter strain and certain "true neisseriae". Still, the acinetobacters constituted one single cluster separated from the other genera of Neisseriaceae.