- Volume 26, Issue 3, 1976

The deoxyribonucleic acids (DNA) of Fusobacterium polymorphum ATCC 10953 and F. fusiforme ATCC 23726 were submitted to DNA-DNA hybridization procedures. A polynucleotide homology of 78% was demonstrated, indicating that the recent grouping of all oral Fusobacterium strains into one species, F. nucleatum, should be reevaluated. The polynucleotide homology between Leptotrichia buccalis ATCC 19616 and the two strains of Fusobacterium tested was less than 30%. The guanine plus cytosine (G+C) values of the DNA of Fusobacterium and Leptotrichia strains tested were similar and unusually low (24.5 to 25.6 mol%). Since bacteria of the family Bacteroidaceae reportedly have G+C values of 41 to 42 mol%, the placing of the genera Fusobacterium and Leptotrichia into this family is questionable. The similar unusually low G+C values of the DNA of Fusobacterium and Leptotrichia may indicate a close phylogenetic relationship for these genera.

The phylogenetic position of Sporosarcina ureae was reexamined by “comparative cataloging” of its 16S ribosomal ribonucleic acid. The data were analyzed in the context of similar information for Micrococcus luteus (Sarcina lutea), Bacillus pasteurii, B. subtilis, and B. stearothermophilus. It is concluded that S. ureae is best classified as a member of the genus Bacillus in the same subgroup as is B. pasteurii.

This is a report of the second cooperative study, conducted by the International Working Group on Mycobacterial Taxonomy, to standardize and establish reproducibility of tests for classifying and identifying mycobacteria. Five tests that met specified rigorous criteria have already been described (Wayne et al., 1974). In the present report, six additional tests are described which meet these criteria. They are tests for production of niacin and of catalase and for resistance to 10 μg of isonicotinic acid hydrazide (isoniazid) per ml, 1 μg of thiophene 2-carboxylic acid hydrazide per ml, 250 μg of hydroxylamine hydrochloride per ml, and 500 μg of p-nitrobenzoate per ml.

A new species of Streptomyces is described for which the name S. longwoodensis is proposed. The organism produces a polyether ionophorous antibiotic, lysocellin. It is characterized by its gray spore mass color, spiral spore chain with smooth spores, chromogenic reaction on ISP media 1 and 6, and carbon utilization characteristics. It differs from all streptomycetes described previously on the basis of its carbon utilization, protein hydrolysis, and pigment production. The type strain of S. longwoodensis is Roche X-14537 (= ATCC 29251).

Serological and deoxyribonucleic acid-deoxyribonucleic acid homology studies were performed with PG2 and Donetta, the type strains of Mycoplasma agalactiae subsp. agalactiae Wroblewski 1931 and Mycoplasma agalactiae subsp. boυis Hale et al. 1962, respectively. It is concluded that the two subspecies should rather be regarded as two different species. It is proposed, therefore, that M. agalactiae subsp. boυis be elevated to the rank of species. The species name is M. boυis (Hale et al.) comb. nov.

A novel representative of the yeast genus Pichia has been recovered 11 times during 1968, 1971, and 1972. We regard this organism as belonging to a new species, Pichia scutulata, with two varieties: P. scutulata var. scutulata, the type variety; and P. scutulata var. exigua. Strains of both varieties were found in tree exudates but were geographically separated. P. scutulata var. scutulata was isolated from slime exudates and flux-wetted soil of Myoporum trees on the island of Hawaii (six strains), whereas P. scutulata var. exigua was found in fluxes or insect borings of various trees in the state of Washington, and in the province of British Columbia, Canada (five strains). P. scutulata var. exigua differs from P. scutulata var. scutulata by its slower fermentation rate, weak ability to utilize glycerol, and higher maximum temperature for growth. The type strain of P. scutulata var. scutulata is UCD-FST 71-102 (= ATCC 32651 = CBS 6644), and that of P. scutulata var. exigua is UCD-FST 68-979B1 (= ATCC 24185 = CBS 6836).