- Volume 29, Issue 3, 1979

Presumably, two strains that are similar to each other resemble each other with respect to similarity towards a third strain. An attempt to test this concept was made by a numerical analysis of a sample. The correlative similarity coefficient between two strains was defined as a correlative coefficient between their simple matching similarity coefficients to a third strain and was denoted by Sc. The two similarity coefficients were compared and employed for dendrogram preparation. As a result, it appeared that more reasonable clustering of strains was made and that the resemblance of each strain to all the others was well reflected with the use of Sc

The type strain of Bacillus psychrophilus Larkin and Stokes 1967 and that of Bacillus globisporus Larkin and Stokes 1967 are very nearly identical. Therefore these names are regarded as synonyms. On the basis of the rule of priority, B. globisporus is the correct name of this species. B. psychrophilus is thus a later subjective synonym of B. globisporus

Eighteen obligately halophilic psychrophilic Bacillus strains were isolated from Josephine Bank (North East Atlantic) sediment samples collected from different depths. These strains closely resembled those of Bacillus globisporus Larkin and Stokes 1967 (syn.: Bacillus psychrophilus Larkin and Stokes 1967). In contrast to the latter, however, the marine strains had cells which were smaller and which formed terminal or subterminal spores that did not swell the sporangium. The new strains required seawater for growth and did not produce urease. Due to these differences, the marine isolates were placed in a single taxon, Bacillus globisporus subsp. marinus subsp. nov. The type strain of this new subspecies is strain 581 (= ATCC 29841 = DSM 1297).

Deoxyribonucleic acid (DNA) homology was used to examine genetic relatedness among 25 yellow-pigmented strains of group D streptococci and to clarify the possible genetic relatedness of these strains to Streptococcus faecium and Streptococcus faecalis. In all cases, the DNA of the yellow-pigmented strains hybridized with the DNA of S. faecium and S. faecalis at a level of less than 25%. Based on median thermal dissociation temperatures (Tm's) and hybridization tests, the yellow-pigmented strains were divided into two groups (I and II). DNAs of strains in group I had relatively low Tm’s and did not exhibit significant homology with DNA of the herein designated type strain (ATCC 25788) of S. faecium subsp. casseliflavus. The DNAs of group II strains, on the other hand, exhibited high Tm’s and had a high degree of homology with the DNA of the type strain of the above-mentioned subspecies. Three physiological traits were found to be peculiar to group II organisms: ability to grow in the presence of 6.5% sodium chloride, inability to ferment sorbitol, and inability to decarboxylate tyrosine. It is proposed that the group II strains constitute a separate and distinct species. Because the strains presently placed in this species include the type strain of S. faecium subsp. casseliflavus Mundt and Graham, the name of this species, according to the rules of the Bacteriological Code, is Streptococcus casseliflavus (Mundt and Graham) comb. nov.

Eleven strains of Pseudomonas coronafaciens, four strains of P. coronafaciens pathovar zeae, six strains of P. coronafaciens subsp. atropurpurea, two strains of P. striafaciens, and one Pseudomonas sp. were compared by physiological, biochemical, serological, and pathological tests. All strains tested utilized sucrose, glucose, fructose, glycerol, and caprate as sole carbon sources, hydrolyzed Tween 80, reduced litmus milk, and grew at 0°C. All strains were arginine dihydrolase and oxidase negative and all strains failed to hydrolyze starch, reduce nitrate, or grow at 41'C. Cells of all strains were immunofluorescent positive when stained by the indirect immunofluorescence test with antiserum to cells of P. coronafaciens or P. coronafaciens subsp. atropurpurea. No differences among strains were detected in test tube agglutination tests. No significant differences were detected in the susceptibility of Avena sativa (oats), Secale cereale (rye), Triticum aestivum (wheat), Hordeum vulgare (barley), Bromus inermis (smooth bromegrass), B. japonicus (Japanese brome), B. secalinus (chess brome), B. tectorum (cheatgrass), Agropyron repens (quackgrass), Zea mays (maize), or Phleum pratense (timothy) to the different strains. All strains produced toxin in Wooley medium except P. striafaciens and strains of P. coronafaciens subsp. atropurpurea from Italian ryegrass. The present division of strains of P. coronafaciens based on minor differences in pathogenicity and symptomology is untenable.

On the basis of its biological properties (cell morphology, staining reactions, cellular inclusions, guanine plus cytosine content of deoxyribonucleic acid, degree of deoxyribonucleic acid homology with Corynebacterium diphtheriae strain PW8, and pattern of enzymic capacities) and chemical structures (peptidoglycan type, major cell wall polysaccharide, major phospholipids and glycolipid, as well as characteristic cell wall fatty acids), Microbacterium flavum Orla-Jensen (synonym: Mycobacterium flavum Jensen) is renamed Corynebacterium flavescens nom. nov. The specific epithet flavum has been changed “flavescens” in order to avoid the creation of a later homonym of Corynebacterium flavum Kisskalt and Berend 1918. Strain 8 of Orla-Jensen (= ATCC 10340 = NCIB 8707) is herein designated the type strain of C. flavescens. An updated description of the organism is given.

Deoxyribonucleic acids (DNA) were extracted from strains of Actinomyces viscosus and Actinomyces naeslundii and were compared by DNA-DNA hybridization. When their DNAs were compared by hybridization on membrane filters, A. viscosus strains from humans were barely separable from A. naeslundii strains, but A. viscosus strains from hamsters were distinctly different. A. viscosus strains from veterinary infections were identical to human strains. With the use of the more sensitive S1 nuclease hybridization method with DNA from a set of strains that had been used in a numerical taxonomy study, typical A. viscosus strains from humans could be distinguished from typical A. naeslundii strains. A group of atypical A. naeslundii strains could also be delineated. The results generally parallel the taxonomic divisions of these organisms based on serology or numerical taxonomy. A. viscosus strains from humans and A. naeslundii strains are similar but distinguishable, but A. viscosus strains from hamsters are clearly separable.

Clostridium villosum sp. nov., isolated from subcutaneous abscesses of cats, is an obligately anaerobic, rod-shaped, sporeforming, monmotile organism which is gram positive in its early stages of growth and gram negative after 18 to 24 h. All strains of this species produce acetic, isobutyric, butyric, isovaleric, lactic, methylmalonic, and succinic acids from cooked meat-carbohydrate and peptone-yeast extract cultures supplemented with 5% horse serum. All of the strains produce ammonia and liquefy gelatin weakly but do not ferment acids or react in any other biochemical tests performed. The pattern of volatile acids produced, the lack of biochemical activity, the colonial morphology, and the late spore production distinguish C. villosum from other Clostridium species so far described. The type strain of C. villosum is VSB 3349; a culture of this strain has been deposited in the National Collection of Type Cultures under the number 11220.

The morphology of the cells of an organism formerly referred to as a member of Leptospira sp. serovar illini has been studied by electron microscopy. Cells of these strains differ morphologically from the cells of leptospires in the following: (i) cells of the former have cytoplasmic tubules which leptospires do not possess, and (ii) the structure of the basal complex on the flagella of the former is similar to that of gram-positive bacteria, whereas the corresponding structure on the flagella of leptospires is similar to that of gram-negative bacteria. Pillot (J. Pillot, thesis, University of Paris, Paris, France, 1965) proposed in 1965 that leptospires should constitute a family, Leptospiraceae. However, Pillot proposed this name in a thesis, which is not considered to be effective publication. Hence, Leptospiraceae is here proposed as the name of a new family. In consequence of the new morphological evidence presented here together with the data from other publications on the deoxyribonucleic acid base composition and serological and cultural properties of cells of strains of Leptospira sp. serovar illini, it is proposed that this family should consist of two genera: Leptospira Noguchi 1917 and Leptonema gen. nov. The type species of Leptonema is Leptonema illini, and the type strain of this species is strain 3055 (= NCTC 11301).

A parasite of the cladoceran Moina rectirostris Leydig 1860 found near Beltsville, Md. and designated CPB was successfully propagated for morphological and ultrastructural studies by infecting laboratory-reared hosts. An ultrastructural examination of vegetative cells indicated that the parasite was procaryotic. The morphology of CPB was nearly identical to that of Pasteuria ramosa Metchnikoff 1888. Consequently, CPB was considered to be an organism like P. ramosa. An electron microscopic study of CPB provided no evidence of longitudinal fission, a concept which had been proposed for P. ramosa by Metchnikoff, but supported much of Metchnikoff’s original description for P. ramosa. For example, CPB was a parasite of a cladoceran. Primary colonies were cauliflower-like. Daughter colonies were formed by fragmentation of mother colonies and produced quartets, doublets, and single sporangia. A sporangium consisted of a conical stem, a swollen middle cell, and an endogenous spore.

American Type Culture Collection (ATCC) strain 19698 is here proposed as the neotype strain of Mycobacterium paratuberculosis Bergey et al. 1923. No culture of any of the strains on which the original description of this organism was based is known to be extant. A working type, ATCC 12227, is used for vaccine and paratuberculin production, but this strain is atypical of the species in that it lacks most of the distinctive properties of the species, including mycobactin requirement and pathogenicity. ATCC 19698 possesses the characters given in the original description of M. paratuberculosis as well as those of the current concept of this species.