Biomedical subjects

D L Williamson

Publications and source records attributed to D L Williamson.

At least 37 records · Page 2Linked to original sources

PubMed1997

A single bout of concentric resistance exercise increases basal metabolic rate 48 hours after exercise in healthy 59-77-year-old men.

BACKGROUND: It has been shown that basal metabolic rate (BMR) decreases with age. The extent to which some of the decrease can be reversed by exercise in older men and women is unclear. Resistance exercise has been shown to significantly increase muscle mass in older individuals, and because muscle is a highly active metabolic tissue there is potential to increase BMR as a secondary outcome to the training adaptation. METHODS: Twelve healthy men aged 59-77 years performed single-leg knee extension exercise (right and left leg) and bench press lifts (16 sets, 10 reps/set with timed recovery between sets) at 75% of the individual's 3RM. Subjects only performed the concentric phase of the lift. BMR was measured on two separate occasions, once after a nonexercise control period and again 48 hrs after a bout of resistance exercise. RESULTS: BMR was significantly increased (p < .006) 48 hrs after exercise (EX) compared to control (CON) (284.0 +/- 34.0 vs 274.9 +/- 34.0 kJ/hr, respectively). Calculated over a 24-hour period, the energy expenditure corresponded to 1570 +/- 193 and 1627 +/- 193 kcal/24 hr (p < .0002) for the CON and EX measures, respectively. VO2 (L/min) was higher (p < .0002) 48 hrs after the EX bout compared to 48 hrs post-CON (0.232 +/- 0.03 vs 0.225 +/- 0.03 L/min, respectively). CONCLUSION: We conclude that in healthy 59-77-year-old men, an acute bout of resistance exercise causes a sustained increase in BMR that persists for up to 48 hours after exercise.

Aged↗

PubMed1997

Spiroplasma diabroticae sp. nov., from the southern corn rootworm beetle, Diabrotica undecimpunctata (Coleoptera:Chrysomelidae).

Spiroplasma strain DU-1T (T = type strain), which was isolated from hemolymph of the corn rootworm Diabrotica undecimpunctata (Coleoptera:Chrysomelidae), was serologically distinct from other spiroplasma species, groups, and subgroups. Cells of strain DU-1T were shown by light microscopy to be helical motile filaments. Electron microscopy revealed cells bounded by a single cytoplasmic membrane, with no evidence of a cell wall. The organism was not sensitive to 500 U of penicillin per ml. Strain DU-1T grew well in SM-1, M1D, and SP-4 liquid media, in broth supplemented with 1% bovine serum fraction or conventional horse serum, and under both aerobic and anaerobic conditions. This organism did not appear to have a sterol requirement for growth, as has been reported for several other Spiroplasma species or strains. Optimal growth occurred at 32 degrees C, with a doubling time of 0.9 h; strain DU-1T multiplied at 10 to 41 degrees C but failed to grow at 5 or 43 degrees C. It produced acid from glucose but hydrolyzed neither arginine nor urea. The results of reciprocal serologic tests in which antigens or antisera to established Spiroplasma species, groups, subgroups, and putative groups were used indicated that strain DU-1T was serologically distinct. This organism has a DNA guanine-plus-cytosine content of 25 +/- 1 mol% and a genome size of 1,350 kbp. Strain DU-1T is a member of a cluster of fast-growing insect-associated spiroplasmas, as determined by sequence analysis of 16S rRNA. On the basis of the results of this study and previously published data, strain DU-1 (= ATCC 43210) is designated the type strain of a new species, Spiroplasma diabroticae.

Animals↗

PubMed1997

Spiroplasma platyhelix sp. nov., a new mollicute with unusual morphology and genome size from the dragonfly Pachydiplax longipennis.

Spiroplasma strain PALS-1T from the gut of the dragonfly Pachydiplax longipennis was shown to be distinct from other species, groups, and subgroups of the genus Spiroplasma as determined by reciprocal serological metabolism inhibition and deformation tests. However, this strain cross-reacted extensively with representatives of other groups when it was used as an antigen. Electron microscopy of cells of strain PALS-1T revealed cells surrounded by a single cytoplasmic membrane. Light microscopy revealed helical cells that exhibited twisting motility rather than rotatory or flexing motility. Variations in the tightness of coiling were transmitted from one end of the helix to the other. The strain was resistant to penicillin, which confirmed that no cell wall was present. The organism grew well in M1D and SP-4 liquid media under either aerobic or anaerobic conditions. Growth also occurred in 1% serum fraction medium and in conventional horse serum medium. The optimum temperature for growth was 30 degrees C, at which the doubling time was 6.4 h. Multiplication occurred at temperatures from 10 to 32 degrees C. Strain PALS-1T catabolized glucose and hydrolyzed arginine but not urea. The guanine-plus-cytosine content of the DNA was 29 +/- 1 mol%. The genome size was 780 kbp, the smallest genome size in the genus Spiroplasma. Strain PALS-1 (= ATCC 51748) is designated the type strain of a new species, Spiroplasma platyhelix.

Animals↗

PubMed1997

Spiroplasma lineolae sp. nov., from the horsefly Tabanus lineola (Diptera: Tabanidae).

Spiroplasma strain TALS-2T from the viscera of the striped horsefly, Tabanus lineola, collected in Georgia was serologically distinct from other Spiroplasma species, groups, putative groups, and subgroups. Light and electron microscopy of cells of strain TALS-2T revealed helical motile cells surrounded only by a single cytoplasmic membrane. The organism grew in M1D and SP-4 liquid media. Growth also occurred in 1% serum fraction medium and in conventional horse serum medium. Growth in liquid media was serum dependent. The strain passed through 220-nm filter pores, but was retained in filters with 100-nm pores. The optimum temperature for growth was 30 degrees C. Multiplication occurred at temperatures from 20 to 37 degrees C, with a doubling time at the optimum temperature of 5.6 h in M1D broth. Strain TALS-2T catabolized glucose but hydrolyzed neither arginine nor urea. The guanine-plus-cytosine content of the DNA was 25 +/- 1 mol%. The genome size was 1,390 kbp. Six isolates serologically similar to strain TALS-2T were obtained from the same host in coastal Georgia. Three strains closely related to strain TALS-2T were isolated from the horsefly Poeciloderas quadripunctatus in Costa Rica. Strain TALS-2T (= ATCC 51749), a representative of group XXVII, is designated the type strain of a new species, Spiroplasma lineolae (Mollicutes: Entomoplasmatales).

Animals↗

PubMed1997

A model of nonparticipation in alcohol treatment programs.

Why do the vast majority of those who suffer harm from drinking fail to obtain treatment? Based on a review of research literature and educational and treatment program materials, a model of nonparticipation in treatment is proposed whereby particular population groups are separated out according to whether or not they exhibit specified characteristics related to both harm from drinking and attitudes towards treatment. Eleven groups have been identified in the model, each of which has different reasons for failing to seek and/or obtain treatment. It is suggested that differing educational program messages should be sent to each group. While the model does not purport to be wholly inclusive of all nonparticipation, it offers a basis for addressing the variety of disparate groups that suffer harm from drinking but do not obtain treatment.

Alcoholism↗

PubMed1996

Spiroplasma diminutum sp. nov., from Culex annulus mosquitoes collected in Taiwan.

Initially, strain CUAS-1T (T = type strain), which was isolated from a frozen triturate of Culex annulus mosquitoes collected in Taiwan, was thought to be a member of spiroplasma group VII. This placement was based on the spiroplasma deformation test titer observed when strain CUAS-1T spiroplasmas were tested with Spiroplasma monobiae MQ-1T antiserum. The results of subsequent reciprocal spiroplasma deformation, metabolism inhibition, and growth inhibition tests clearly revealed that strain CUAS-1T is not serologically related to previously described spiroplasma groups (groups I to XXIV) and thus is a representative of a new group, group XXV. Strain CUAS-1T was characterized by using the minimal standards for mollicute species descriptions. During logarithmic-phase growth, strain CUAS-1T cells are characteristically very short helices with 1.5 to 2 helical turns (1 to 2 microns), highly motile, and bounded by a single trilaminar membrane and form granular colonies with satellites when the organism is grown aerobically on MID medium containing 1.6% agar. Growth in MID broth occurs at temperatures ranging from 10 to 37 degrees C, and the optimum temperature is 30 degrees C. Substrate utilization tests revealed that cholesterol is required for growth, that glucose is hydrolyzed, and that arginine is not hydrolyzed both in the presence and in the absence of glucose. The genome of strain CUAS-1T is 1,080 kbp long, and the guanine-plus-cytosine content is 26 +/- 1 mol%. On the basis of the results of our studies we propose that strain CUAS-1T (group XXV) should be placed in a new species, Spiroplasma diminutum. Strain CUAS-1 (= ATCC 49235) is the type strain of S. diminutum.

Animals↗

PubMed1996

Spiroplasma syrphidicola sp. nov., from a syrphid fly (Diptera: Syrphidae).

Spiroplasma sp. strain EA-1(T) (T = type strain) (subgroup VIII-1), which was isolated from the syrphid fly Eristalis arbustorum, was serologically distinct from other spiroplasma species, groups, and subgroups, The cells of this strain, as revealed by dark-field light microscopy, were short, helical, and motile. An electron microscopic examination revealed wall-less cells delimited by a single membrane. The unusually short cells passed through 220-nm filter pores with no reduction in titer. The organisms grew well in SM-1, M1D, and SP-4 liquid media. Growth also occurred in conventional horse serum medium and 1% serum fraction medium. Strain EA-1(T) grew at temperatures between 10 and 41 degrees C, and optimum growth occurred at 32 degrees C. The doubling time at the optimal temperature was 1.0 h. The strain catabolized glucose and hydrolyzed arginine but did not hydrolyze urea. The guanine-plus-cytosine content of the DNA was 30 +/- 1 mol%. The genome size was about 1,230 kbp. Strain Ea-1 (= ATCC 33826), which represents subgroup VIII-1, is designated the type strain of a new species, Spiroplasma syrphidicola.

Animals↗

PubMed1996

Spiroplasma corruscae sp. nov., from a firefly beetle (Coleoptera: Lampyridae) and tabanid flies (Diptera: Tabanidae).

Spiroplasma strain EC-1T (T = type strain), which was isolated from the gut of a lampyrid beetle (Ellychnia corrusca) in Maryland, was serologically distinct from other spiroplasma species and groups. Similar strains were obtained from other E. corrusca specimens, and, later, numerous isolates of similar or partially related strains were obtained from several species of tabanid files. Cells of strain EC-1T were helical, motile filaments that were bound by a single cytoplasmic membrane, and there was no evidence of a cell wall. The cells were filterable through 220-nm-pore-size membrane filters but not through 100-nm-pore-size membrane filters. The organism was absolutely resistant to penicillin (1,000 U/ml) and required sterol for growth. Strain EC-1T grew well in M1D and SP-4 liquid media and could be cultivated in the Edward formulation of conventional mycoplasma medium and in 1% serum fraction medium. Optimal growth occurred at 32 degrees C (doubling time, 1.5 h). Strain EC-1T multiplied at 10 to 41 degrees C, but not at 5 or 43 degrees C. This organism produced acid from glucose, but did not hydrolyze arginine or utilize urea. The guanine-plus-cytosine content of the DNA was determined to be 26.3 mol% by the melting temperature method and 27.0 mol% by the buoyant density method. As a result of our studies, strain EC-1 (= ATCC 43212) is designated the type strain of a new species, Spiroplasma corruscae.

Animals↗

PubMed1996

Improved cultivation systems for isolation of the colorado potato beetle spiroplasma.

In North America, the Colorado potato beetle, Leptinotarsa decemlineata, is often infected with the host-specific, gut-inhabiting Colorado potato beetle spiroplasma (CPBS). CPBS is apparently a commensal, but it may be useful in biocontrol if it can be transformed to express an insect-lethal gene. Difficulty in cultivating the organism, however, has hindered the development of a suitable transformation system. In this study, we eliminated the need for coculturing CPBS with insect cells. CPBS was reliably isolated with the BBL Anaerobic GasPak Jar system (low redox, enhanced CO(inf2)), which was easier to use and less expensive than insect cell coculture methods. A further advantage is a reduction in contaminating insect cell components. Use of anaerobiosis should facilitate early-passage screening of isolates for extrachromosomal elements, for use in gene vector constructs. The unique spiral (decreasing amplitude of coils) morphology of CPBS was preserved by anaerobiosis. The use of low-pH (6.0 to 6.5) media allowed aerobic adaptation of CPBS to M1D and SP-4 broth media. These formulations permitted the first cultivation of CPBS on solid media, an accomplishment that will simplify the selection of molecular transformants. Potato beetles collected at four sites in Poland yielded CPBS strains similar to those previously obtained from populations in North America.

Journal Article↗

PubMed1995

Spiroplasma ixodetis sp. nov., a new species from Ixodes pacificus ticks collected in Oregon.

Eight strains of mollicutes were isolated from pooled suspensions prepared from western black-legged ticks (Ixodes pacificus) collected in Oregon. Morphologic examination by electron and dark-field microscopic techniques showed that each strain consisted of a mixture of motile, tightly coiled helical cells, small coccoid cells with diameters ranging from 300 to 500 nm, and pleomorphic, straight or branched filamentous forms. All cellular forms were surrounded by a single cytoplasmic membrane, and there was no evidence of a cell wall. The organisms were filterable and fastidious in their growth requirements. The optimum temperature for growth was 30 degrees C, but multiplication occurred at temperatures ranging from 23 to 32 degrees C. The strains catabolized glucose but did not hydrolyze arginine or urea. The genome size of strain Y32T (T = type strain) was 2,220 kbp, and the DNA base composition (guanine-plus-cytosine content) of this organism was 25 +/- 1 mol%. The eight isolates were serologically related to each other but were not related to 37 other type or representative strains belonging to the genus Spiroplasma. Strain Y32 (= ATCC 33835) is the type strain of Spiroplasma ixodetis sp. nov.

Animals↗

PubMed1995

Spiroplasma velocicrescens sp. nov., from the vespid wasp Monobia quadridens.

Spiroplasma strain MQ-4T (T = type strain), which was isolated from the hemolymph of the vespid wasp Monobia quadridens, was serologically distinct from other spiroplasma species, groups, putative groups, and subgroups. Each strain MQ-4T cell was helical and motile and was surrounded by a single cytoplasmic membrane; there was no evidence of a cell wall. The strain grew well in 1% serum fraction medium, as well as in SM-1, M1D, and SP-4 liquid media, under both aerobic and anaerobic conditions. Strain MQ-4T grew at temperatures ranging from 10 to 41 degrees C but did not grow at 43 degrees C. The strain grew optimally at 37 degrees C with a doubling time of 0.6 h, the shortest doubling time recorded for any spiroplasma. Strain MQ-4T catabolized glucose and arginine but did not hydrolyze urea. The guanine-plus-cytosine content of the DNA was about 27.5 +/- 1 mol%. The genome size was 1,480 kbp (940 MDa). Strain MQ-4 (= ATCC 35262) is designated the type strain of a new species, Spiroplasma velocicrescens.

Animals↗

PubMed1995

Harmful effects of drinking and the use and perceived effectiveness of treatment.

OBJECTIVE: The objectives of the study were to examine relationships between: (1) harmful effects of drinking and use of treatment services, (2) the number of different types of harm experienced and whether or not treatment was obtained, and (3) the types of treatment obtained and the perceived effectiveness of treatment. METHOD: A secondary analysis was carried out of data obtained from the Canadian National Alcohol and Other Drugs Survey, conducted by Statistics Canada in 1989. The sample consisted of 1,954 respondents who reported experiencing at least one of six specified harmful effects from drinking. Chi-square tests were used to test relationships, with the alpha level set at 0.01. RESULTS: While 21.5% of all current drinkers suffered at least one type of harm, only 10.6% of these obtained treatment (Objective 1). The number of harmful effects experienced is directly related to the likelihood of obtaining treatment: only 3.8% of those who had experienced one type of harm received treatment compared to 41.6% of those suffering all six types of harm (Objective 2). Almost three-quarters (73.8%) of those who received treatment obtained it through self-help groups such as Alcoholics Anonymous. While the findings about perceived effectiveness of treatment are tenuous because of the small numbers involved, more than half (52.0%) of those who had used self-help groups rated them as very effective, with most of the remainder (43.2%) rating them as moderately effective (Objective 3). CONCLUSIONS: The results confirm the contention that those who suffer harm from drinking are often difficult to involve in treatment. They also show, however, that the greater the number of harmful effects experienced, the more likely it is that a person will obtain treatment, suggesting that those most harmed are easiest to involve in treatment. The findings also emphasize that self-help groups are the overwhelmingly preferred mechanism for those who do obtain treatment, perhaps because of their greater accessibility and flexibility. Also, although the least reported harmful effect was on work, studies and employment, persons suffering this type of harm were the most likely to obtain treatment, suggesting that others affected by the harmed person may play a significant role in influencing him or her to obtain treatment.

Adult↗

PubMed1994

Effect of polyethylene fiber reinforcement on the strength of denture base resins polymerized by microwave energy.

This study investigated the effect of addition of polyethylene fibers on the transverse strength, deflection, and elastic modulus of two denture base acrylic resins polymerized by microwave irradiation. Specimens of each resin, Lucitone 199 and Acron MC, were fabricated with 0.0%, 0.5%, 1.5%, and 3.0% fiber loading. Specimens were tested with use of a three-point flexure apparatus with an Instron universal testing machine after storage in water for 10 days at 37 degrees C. The results showed that polyethylene fibers significantly decreased the transverse strength of Acron MC resin and slightly increased the transverse strength of Lucitone 199 resin at a loading of 0.5% by weight. Fiber loading did not significantly affect the deflection and the elastic modulus of either material.

Acrylic Resins↗

PubMed1994

Acholeplasma brassicae sp. nov. and Acholeplasma palmae sp. nov., two non-sterol-requiring mollicutes from plant surfaces.

Two mollicutes (strains 0502T [T = type strain] and J233T), which were isolated from the surfaces of broccoli (Brassica oleracea var. italica) plants or the crown tissues of the coconut palm (Cocos nucifera), were capable of sustained growth in serum-free (or cholesterol-free) mycoplasma broth media. Examination by electron and dark-field microscopic techniques revealed that the cells of each strain were small, nonhelical, nonmotile, pleomorphic, and coccoid and that each cell was surrounded by a single cytoplasmic membrane. No evidence of a cell wall was found. The organisms were filterable and grew rapidly in most conventional mycoplasma culture medium formulations containing horse or fetal bovine sera under either aerobic or anaerobic conditions. The optimum temperature for growth of both organisms was 30 degrees C, but multiplication occurred over a temperature range from 18 to 37 degrees C. Both strains catabolized glucose, but did not hydrolyze arbutin, arginine, or urea. The genome size of strain 0502T was 1,215 kbp, and the DNA base composition (guanine-plus-cytosine content) was 35.5 mol%. The genome size of strain J233T was 1,610 kbp, and the DNA base composition was 30.0 mol%. The two isolates were not serologically related to each other or to the type strains of 11 previously described Acholeplasma species. Strain 0502 (= ATCC 49388) is the type strain of Acholeplasma brassicae sp. nov., and strain J233 (= ATCC 49389) is the type strain of Acholeplasma palmae sp. nov.

Acholeplasma↗

PubMed1994

Taxonomic descriptions of eight new non-sterol-requiring mollicutes assigned to the genus Mesoplasma.

Twenty mollicute strains isolated primarily from insect hosts were characterized and arranged into eight new species in the genus Mesoplasma. Morphological examination of the organisms by electron and dark-field microscopic techniques revealed that the cells of each strain were small, nonhelical, nonmotile, pleomorphic, and coccoid and that each cell was surrounded by a single cytoplasmic membrane with no evidence of a cell wall. Although the new mollicutes grew well in media containing horse or fetal bovine serum, growth in serum-free or cholesterol-free medium occurred only when the medium contained 0.04% polyoxyethylene sorbitan (Tween 80). The optimum temperature for growth was usually 30 degrees C, but multiplication generally occurred over a temperature range of 10 to 32 degrees C. All strains catabolized glucose. Most strains did not hydrolyze arginine or urea, although three related strains isolated from fireflies (the strain PUPA-2T [T = type strain] group) did hydrolyze arginine. The genome sizes ranged from 825 to 930 kbp, and the DNA base compositions (guanine-plus-cytosine contents) ranged from 26.5 to 31.6 mol%. The proposed type strains of the eight new species were not serologically related to the type strains of four other Mesoplasma species, five Entomoplasma species, 11 Acholeplasma species, and 100 Mycoplasma species and subspecies. Strain PS-1 (= ATCC 49582) is the type strain of Mesoplasma pleciae sp. nov., strain PUPA-2 (= ATCC 49581) is the type strain of Mesoplasma photuris sp. nov., strain YJS (= ATCC 51578) [corrected] is the type strain of Mesoplasma syrphidae sp. nov., strain CHPA-2 (= ATCC 49578) is the type strain of Mesoplasma chauliocola sp. nov., strain ELCA-2 (= ATCC 49579) is the type strain of Mesoplasma corruscae sp. nov., strain GRUA-1 (= ATCC 49580) is the type strain of Mesoplasma grammopterae sp. nov., strain BARC 779 (= ATCC 49583) is the type strain of Mesoplasma coleopterae sp. nov., and strain BARC 857 (= ATCC 49584) is the type strain of Mesoplasma tabanidae sp. nov.

Animals↗

PubMed1991

Nucleotide sequence of the Spiroplasma citri fibril protein gene.

Electron microscopic observation of spiroplasmas lysed by detergent (sodium deoxycholate) revealed the release of bundles of fibrils from the cells. Individual fibrils are 4 nm in diameter and possess a 9-nm periodicity along their length. These fibrils are thought to function as cytoskeletal structures involved in the shape and motility of spiroplasmas. Polyacrylamide gel electrophoresis of density gradient-purified fibrils showed a protein of approximately 55 kDa. Oligonucleotide probes were constructed from the N-terminal amino acid sequence of two peptides obtained after V8 protease hydrolysis of the fibril protein. The probes were used to identify the clones in a genomic DNA library of Spiroplasma citri that contained inserts carrying the probe sequence. Sequencing of a 3.3-kbp fragment yielded the full open reading frame of the fibril protein gene and the start of a second open reading frame of an unknown protein. The fibril protein is composed of 515 amino acids, which have a computed molecular mass of 59 kDa. Northern (RNA) blot hybridization and primer extension experiments showed that transcription of the fibril protein gene starts from a promoter located 100 nucleotides upstream of the initiation codon and stops at a rho-independent type terminator, leading to a 1.7-kbp transcript. Southern blot hybridization of genomic DNA using the fibril protein gene as the probe showed that a single copy of the gene is present in the chromosomes of both S. citri and Spiroplasma melliferum. The genotypic symbol fib is proposed for the spiroplasma fibril protein gene.

Amino Acid Sequence↗

PubMed1990

Mycoplasma lactucae sp. nov., a sterol-requiring mollicute from a plant surface.

Strain 831-C4T (T = type strain), isolated from the surface of lettuce plants (Lactuca sativa) obtained from a retail food market, was shown to be a sterol-requiring mollicute. Morphological examination of this organism by electron and dark-field microscopic techniques showed that it consists of small, nonhelical, nonmotile, pleomorphic coccoid cells, with individual cells surrounded by a single cytoplasmic membrane. No evidence of a cell wall was observed. The organism grew rapidly in all conventional culture medium formulations for mollicutes in either aerobic or anaerobic environments. The optimum temperature for growth was 30 degrees C, but multiplication occurred at 18 to 37 degrees C. Strain 831-C4T catabolized glucose, but hydrolysis of arginine or urea could not be demonstrated. The genome size of strain 831-C4T was determined to be about 569 megadaltons, while the base composition (guanine-plus-cytosine content) of the DNA was 30.0 mol%. Recent studies in which we compared the 16S rRNA sequences of strain 831-C4T with those of more than 40 other mollicutes indicated that this organism is phylogenetically related to the Spiroplasma-Mycoplasma mycoides clade. Strain 831-C4T was serologically unrelated to the type strains of previously described Mycoplasma species and to 18 other unclassified sterol-requiring isolates cultivated from various animal, plant, or insect sources. Strain 831-C4T (= ATCC 49193) is the type strain of Mycoplasma lactucae sp. nov.

Mycoplasma↗

PubMed1990

Mycoplasma somnilux sp. nov., Mycoplasma luminosum sp. nov., and Mycoplasma lucivorax sp. nov., new sterol-requiring mollicutes from firefly beetles (Coleoptera: Lampyridae).

Strain PYAN-1T (T = type strain), which was isolated from a pupal gut of the firefly beetle Pyractonema angulata, and strains PIMN-1T and PIPN-2T, which were isolated from guts of adult Photinus marginalis and Photinus pyralis fireflies, respectively, were demonstrated to be sterol-requiring mollicutes. Cells of the three strains were shown by electron and dark-field microscopy to be small, pleomorphic, nonhelical, nonmotile bodies surrounded by single membranes. No evidence of a cell wall was observed, and the organisms were not susceptible to 500 U of penicillin per ml. The three strains grew rapidly in SP-4 broth medium. Strains PIMN-1T and PIPN-2T grew in medium supplemented with bovine serum fraction, but strain PYAN-1T did not. All three strains grew on solid media when the cultures were incubated aerobically, but only strains PYAN-1T and PIPN-2T formed colonies when anaerobic conditions were employed. The three strains catabolized glucose but hydrolyzed neither arginine nor urea. All of the strains grew at temperatures of 18 to 32 degrees C; strains PYAN-1T and PIMN-1T also grew at 10 degrees C. The optimal temperature for growth for strains PYAN-1T and PIPN-2T was 30 degrees C; strain PIMN-1T grew equally well at 30 or 32 degrees C. None of the three strains grew at 37 degrees C. The genome sizes of strains PYAN-1T, PIMN-1T, and PIPN-2T were about 527 (478 to 589), 570 (480 to 630), and 762 (635 to 871) megadaltons, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗