Wall-less prokaryotes from fall flowers in central United States and Maryland

100

Twenty-eight strains of spiroplasma subgroup 1-2 isolated from insects and flower surfaces were similar in their serological properties. Strain BC-3T (T = type strain), which was isolated from the honeybee, was chosen as a representative of this cluster and was characterized according to accepted standards. This strain and other strains of the cluster entered the hemocoel of their insect hosts after per 0s acquisition, caused pathology in various tissues, and reduced adult longevity. Growth in SM-1 or M1D medium occurred at 20 to 37"C, with optimum growth at about 32 to 35°C. Cholesterol was required for growth. Glucose, fructose, and other carbohydrates were fermented, and arginine was catabolized. Seventeen strains, including strain BC-3T, reacted with considerable homogeneity in deformation tests and were completely separable from strains of subgroup 1-1 (Spiroplusmu citri) and subgroup 1-3 (corn stunt spiroplasma). A group of five subgroup 1-2 strains showed homogeneity upon one-dimensional polyacrylamide gel electrophoresis of cell proteins. Strain BC-3T was also serologically distinct from subgroups 1-4 through 1-8; from Spiroplusmu JEoricolu, Spiroplusmu upis, and Spiroplasma mirum; and from representative strains of spiroplasma groups I1 and VI through XI. Previously published studies on strain BC-3T and related strains demonstrated that (i) these organisms comprise a unique subgroup of the S. citri complex (group I); (ii) deoxyribonucleic acid-deoxyribonucleic acid homologies between strain BC-3T and strains of other group I subgroups do not exceed 70%; (iii) the patterns of protein sharing among group I strains revealed by two-dimensional polyacrylamide gel electrophoresis support molecular genetic indications of partial relatedness; (iv) the EcoRI restriction endonuclease patterns of deoxyribonucleic acids from strain BC-3T and serologically related strains show close relatedness; (v) sequencing of 5s ribosomal ribonucleic acid suggests some degree of relatedness with all organisms now classified in the Mollicutes; (vi) strain BC-3T is capable of viscotactic and chemotactic responses; (vii) strain BC-3T possesses fibrils that may mediate various types of motility; and (viii) a lytic virus (SpV4) isolated from Spiroplusmu sp. strain B63 (a representative of subgroup 1-2) is morphologically and genomically distinct from other spiroplasma viruses and forms plaques only on lawns of subgroup 1-2 spiroplasmas. Previous work on strain AS 576, another member of subgroup 1-2, demonstrated (i) a viscotactic response, (ii) moderate sensitivity to osmotic environments, (iii) susceptibility to tetracycline and aminoglycoside antibiotics, (iv) growth in a relatively simple, chemically defined medium, (v) nutritional utilization patterns in defined medium, and (vi) a genome molecular weight of lo9. On the basis of our new findings and the previously described properties of strain BC-3T and related subgroup 1-2 strains, we propose that spiroplasma strains with the characteristics described here be classified as a new...

supporting

confidence: 57%

mentioning

confidence: 99%

Spiroplasma melliferum, a New Species from the Honeybee (Apis mellifera)

Clark

Whitcomb

Tully

et al. 1985

100

“…Subsequent characterization of these strains and other new isolates from plant surfaces (22) showed that some of the strains were related to established sterol-nonrequiring Acholeplasma species that occur in vertebrate hosts (e.g., Acholeplasrna axanthum , Acholeplasma oculi, and Acholeplasma laidlawii) (9,22). Other isolates represented either new Acholeplasma species (14,33) or possibly sterol-requiring Mycoplasma species (9,22,26).…”

mentioning

confidence: 99%

Acholeplasma seiffertii sp. nov., a Mollicute from Plant Surfaces

Bonnet¹,

Saillard²,

Vignault³

et al. 1991

Two mollicutes (strains F7T [T = type strain] and F28) isolated from floral surfaces of plants growing in Morocco and France were capable of sustained growth in serum-free (or cholesterol-free) mycoplasma broth media. The two isolates were found to be genomically and serologically related. Morphologic examination of the organisms by electron and dark-field microscopic techniques showed that each strain consists of small, nonhelical, nonmotile, pleomorphic coccoid cells surrounded by a single cytoplasmic membrane. No evidence of cell walls was observed. Growth in serum-free or cholesterol-free medium was sustained only when the medium contained a Tween 80 fatty acid mixture (0.01 or 0.04%). The organisms grew rapidly in most conventional mycoplasma culture medium formulations containing horse or fetal bovine serum or a bovine serum fraction and under either aerobic or anaerobic environments. The optimum temperature for growth was 28"C, but multiplication occurred over a temperature range from 20 to 35°C. Both strains catabolized glucose and mannose, but did not hydrolyze arbutin, arginine, or urea. The molecular mass of the genome of strain F7T was determined to be about 886 megadaltons, while the base composition (guanine-plus-cytosine content) of the DNA was found to be 30.0 mol%. The two isolates were serologically unrelated to type strains of the 11 previously described Acholeplasma species and to 10 other unclassified sterol-nonrequiring mollicutes cultivated from various animal, plant, or insect sources. Strain F7 (= ATCC 49495) is the type strain of Acholeplasma seiflertii sp. nov.The occurrence of nonhelical, wall-less prokaryotes (class Mollicutes) on plant surfaces was first well documented in 1979 (9,15) when organisms with the general features of both Acholeplasma and Mycoplasma species were isolated from the surfaces of several tropical floral plants. Subsequent characterization of these strains and other new isolates from plant surfaces (22) showed that some of the strains were related to established sterol-nonrequiring Acholeplasma species that occur in vertebrate hosts (e.g., Acholeplasrna axanthum , Acholeplasma oculi, and Acholeplasma laidlawii) (9, 22). Other isolates represented either new Acholeplasma species (14, 33) or possibly sterol-requiring Mycoplasma species (9,22,26).While the presence of sterol-requiring Mycoplasma species on plant surfaces was suspected from the studies reported in 1979 to 1982 (15, 22), the possibility that these organisms might represent sterol-requiring, nonhelical forms of the genus Spiroplasrna could not be excluded at the time. The occurrence of Mycoplasma species on plant surfaces was confirmed recently when two of the strains from the early studies (17, 29) were fully characterized. In addition, sterol-requiring mollicutes were isolated from insect guts and from hemolymph samples (30), and four of these strains were characterized recently as new insect-derived Mycoplasma species (28, 34).The natural occurrence of acholeplasmas in the guts and hemolymph of in...

“…We have reported previously that the two feline and four canine ureaplasma serogroups are serologically distinct from each other and from the three established species (9,(13)(14)(15)(16). Although serological procedures are useful, DNA hybridization techniques have been especially successful in resolving taxonomic relatedness among various strains and species within the genera Acholeplasma (2), Anaeroplasma (23), Mycoplasma (4), Spiroplasma (28), and Ureaplasma (7). For these reasons, we used the same DNA hybridization techniques to compare the genomic relationships among strains belonging to the two unclassified feline serogroups, the four unclassified canine serogroups, and the three previously established Ureaplasma species.…”

mentioning

confidence: 99%

DNA Relatedness among Established Ureaplasma Species and Unidentified Feline and Canine Serogroups

Harasawa

Stephens

Koshimizu

et al. 1990

The levels of DNA relatedness among two unclassified feline ureaplasma serogroups, four unclassified canine ureaplasma serogroups, and the three previously established Ureuplasmu species were examined and compared. The strains examined included five feline strains representing two feline serogroups, four canine strains representing four canine serogroups, and the type strains of the three established species. Each strain representing each species or serogroup exhibited 78% or more actual DNA homology with its homologous DNA, but less than 10% DNA homology with DNAs from the heterologous strains. These findings indicate that each of these human, bovine, avian, feline, and canine strains is genomically distinct. In addition, the three previously recognized species (UreupZusma ureulyticum [human], Ureaplusmu diversum [bovine], and Ureuplusmu gallorule [avian]), which were established on the basis of phenotypic properties, were also shown to be genomically distinct. The three feline serogroup SI strains were genomically related (from 89 to 100% DNA homology) to each other but were unrelated (less than 10% DNA homology) to the feline serogroup SII strains, indicating that these two feline serogroups are also genomically distinct. Conversely, the two feline serogroup SII strains were genomically very similar (from 83 to 100% DNA homology) to each other but were unrelated (less than 10% DNA homology) to the three feline serogroup SI strains. However, canine serogroup SI strain D1M-C exhibited 73 % DNA homology with serologically distinct canine serogroup SII strain D29M, indicating that these strains representing two separate serogroups belong to the same genomic species. Our findings indicate that the two feline ureaplasma serogroups and at least one canine ureaplasma serogroup are genomically distinct and are unrelated to the previously established species and that each serogroup represents a new species or subspecies within the genus Ureaplusmu.