- Volume 26, Issue 1, 1976

A collection of 178 strains of staphylococci from human skin, representing the three generally accepted species (Staphylococcus aureus, S. epidermidis, and S. saprophyticus ) and seven recently proposed new species (S. simulans, S. cohnii, S. xylosus, S. warneri, S. capitis, S. haemolyticus, and S. hominis ), was studied with regard to their requirements for uracil and pyruvate for anaerobic growth. S. saprophyticus and six of the proposed new species required both of these nutrients for good anaerobic growth and achieved essentially no growth when both were absent from the medium. S. simulans was unique in having no requirement for these nutrients for vigorous anaerobic growth. Only eight strains, six of S. cohnii and two of S. haemolyticus, gave no anaerobic growth in the medium with both uracil and pyruvate. Many strains of S. epidermidis and S. aureus grew well when both substances were absent but grew somewhat better when one or both were present. The taxonomic implications of this study provide some support for acceptance of several of the proposed new species.

Several strains previously classified as group III staphylococci, by the scheme of Schleifer and Kocur, and numerous strains isolated from animal and human skin that appeared to be related to group III strains were subjected to a taxonomic study. As a result of this study, all group III and related strains were placed in the newly proposed species Staphylococcus sciuri. This species can be differentiated from all other staphylococci on the basis of colony morphology, cell wall peptidoglycan, acid production from cellobiose and usually from fucose under aerobic conditions, and a combination of other characteristics. Thirty-five strains that produced large colonies, usually moderate to light anaerobic growth in thioglycolate, and acid from galactose, sucrose, glycerol, and often from melezitose were placed in the type subspecies, S. sciuri subsp. sciuri. Nine strains that produced very small, unpigmented colonies, usually no detectable anaerobic growth in thioglycolate, and acid from sucrose and often from galactose, glycerol, lactose, and raffinose were placed in the subspecies S. sciuri subsp. lentus. The type strains of these subspecies are ATCC 29062 and ATCC 29070, respectively. A group of three strains that produced relatively small, unpigmented colonies, moderate anaerobic growth in thioglycolate, and acid from glycerol but failed to produce acid from sucrose, melezitose, raffinose and usually galactose may also deserve subspecies status. A summary of the character variation found in S. sciuri and in other novobiocin-resistant species and a simplified scheme for distinguishing S. sciuri and its subspecies are included in this paper.

Serological techniques have been used to detect small changes in amino acid sequences of specific proteins in closely related biological systems. These changes are believed to reflect evolutionary divergence. In the present study, the differences in binding capacities of catalases from different mycobacteria for a reference antiserum were measured very specifically by assaying the unbound functional enzyme after exposure to antibody. Catalase derived from Mycobacterium tuberculosis has been used to immunize rabbits. The antibody so produced precipitated the enzyme but did not inactivate it. This antibody also precipitated catalase from sonic lysates of other mycobacterial species. The binding capacity of catalase derived from a number of heterologous species for the M. tuberculosis antibody was always lower than that of homologous enzyme. Some species produced catalase that failed to react at all with the reference serum. In other cases, there was evidence of at least two serologically unrelated catalases in a single strain. There was also a limited correlation between rate of inactivation of catalase by heat and the relative antibody-binding capacity of the enzyme. The serological study of catalases offers promise of providing a useful tool for clarifying evolutionary relationships among mycobacterial species.

The micromorphology, ultrastructure, and cell wall composition of an actinomycete isolated from beach sand were studied. On the basis of its cell wall composition and some of its morphological features, it was placed in the genus Streptosporangium. It differed from other members of this genus by producing rather ill-defined sporangia containing thick-walled, ridged spores together with short chains of similar spores. This organism is regarded as belonging to a new species, for which we propose the name Streptosporangium corrugatum. The type strain of this species is E90 (NCIB 11120).

National Research Council of Canada (NRCC) strain 14033 is a gram-variable, motile, yellow-pigmented, strictly aerobic, facultatively halophilic coccus. The guanine plus cytosine content of the deoxyribonucleic acid of this strain is 50.4 ± 0.7 mol%. This strain belongs to the genus Planococcus but differs from the neotype strain (CCM 316) of the type species, Planococcus citreus, in cell wall composition and NaCl requirement; unlike strain CCM 316, strain NRCC 14033 possesses meso-diaminopimelic acid in its cell wall peptidoglycan, and it cannot grow on nutrient medium at 30 C without added NaCl. We regard this strain as belonging to a new species, for which we propose the name Planococcus halophilus. Since the original description is based on a single strain, this strain is the type strain by monotypy. It has been deposited in the American Type Culture Collection under the number 27964.

The properties of 17 strains of a nocardioform actinomycete isolated from soil are described. The hyphae of the primary mycelium of this organism fragment into irregular to rod- to coccus-like elements. The hyphae of the aerial mycelium fragment into rod- to coccus-like elements with smooth surfaces. These elements give rise to new mycelia. The organism is a gram-positive, non-acid-fast, aerobic, mesophile, and it has a cell wall composition of type I (LL-diaminopimelic acid, alanine, glutamic acid, glycine). The deoxyribonucleic acid base composition is 66.5 mol% G+C. The actinomycete is susceptible to phages of a taxon-specific set. Polyvalent Nocardia and Streptomyces phages are not propagated in the nocardioform organism, which is here regarded as belonging to a new genus, Nocardioides, the type species of which is N. albus. The type strain of N. albus is IMET 7807 (Culture Collection of the Zentralinstitut für Microbiologie und experimentelle Therapie, Jena). It has been deposited in the American Type Culture Collection under the number 27980. The new genus is placed in the family Streptomycetaceae.

Corynebacterium diphtheriae and closely related corynebacteria are gram-positive, pleomorphic, facultatively anaerobic bacteria which have been classified (in part) according to their capacity to reduce or not reduce nitrates to nitrites. An investigation of the presence or absence of nitrate reductase activity in C. diphtheriae, in particular, and in C. belfanti, C. ulcerans, C. ovis, C. hofmanni, and C. xerosis, in general, indicates that (i) the control of the synthesis of the enzyme is a readily mutable property, (ii) enzyme synthesis occurs under anaerobic conditions, and (iii) maximal activity is associated with the “pellet” or “membrane” fraction. Additional evidence indicates that the gene N-red is not on the phage chromosome and, therefore, is not linked to the gene governing the synthesis of diphtherial toxin (tox) as previously claimed.

A new family name, Chloroflexaceae, is introduced for the phototrophic, gliding, filamentous bacteria containing chlorobium vesicles and bacteriochlorophylls c and a. The type genus in Chloroflexus Pierson and Castenholz with type species Chloroflexus aurantiacus Pierson and Castenholz 1974.

O antigens 0149 to 0163 are recent additions to the Escherichia coli antigenic scheme. Their antigenic relationships with Shigella serovars were examined. O antigen identity was demonstrated between E. coli 0149 and Shigella boydii 1 and between E. coli 0152 and provisional Shigella serovar 3341-55. A reciprocal relationship was found between E. coli 0159 and Shigella dysenteriae 4 but identity was not demonstrated. The remaining E. coli O antigens were not significantly related to any Shigella serovar.

A new agar medium, DMS agar, which combines dulcitol and salicin fermentation with malonate utilization, is described for use in differentiating Salmonella subgenera.

The phage types of 77 caulobacters were determined using 26 phages specific for this group of stalked bacteria. A standardized procedure, utilizing routine test dilutions, was used to eliminate an inhibition phenomenon which accounted for 53% of the positive reactions when undiluted phage lysates were tested. Among productive hosts, Caulobacter and Asticcacaulis phages were genus specific, although this specificity was not demonstrated by the inhibition reactions. However, Asticcacaulis ϕ20S was specific for only 2 of the 15 eccentrically stalked isolates tested. This limited specificity was common among the phages regardless of the cellular morphology of their host, since 7 of the 16 phages having productive hosts had no more than 2 hosts. Without phages that were specific for a broad host range of eccentrically stalked caulobacters, the separation of the genera Caulobacter and Asticcacaulis was not supported by bacteriophage typing.

Actinomyces bovis ATCC 13683 and A. israelii ATCC 12102 are described, and they are here designated as the neotype strains of these two species.