| variation in the susceptibility of bovine mycoplasmas to killing by the alternative complement pathway in bovine serum. | all but one of nine acholeplasma strains were susceptible to killing by gnotobiotic-calf serum while all but one of fifteen mycoplasma strains were resistant. the mechanism of killing was examined using inhibitors of complement, viz. edta. mgegta. epsilon-amino caproic acid, and also by desalting serum and adding mgcl2 and cacl2. the results indicated that, when strains were killed by serum from gnotobiotic calves it was by the alternative complement pathway. however, experiments with mycoplasma ... | 1980 | 7007210 |
| the structure and functions of the mycoplasma membrane. | | 1981 | 7012066 |
| a note on positive bactec readings produced by mycoplasma. | | 1981 | 7024236 |
| isolation of acholeplasmas and a mycoplasma from vegetables. | the isolation of mollicutes from food has not been reported. to isolate mollicutes in the presence of high levels of unwanted bacteria, we first incubated fresh vegetables in liquid culture media containing lysozyme, ampicillin, and thallous acetate. culture fluids were than separated from the vegetable samples, subjected to one freeze-thaw cycle, and passed through a filter of 0.4-micron porosity. filtered samples were cultured in sp4 medium and in a conventional medium containing horse serum. ... | 1982 | 7036899 |
| adsorption of the tailed mycoplasma virus l3 to cell membranes. | the adsorption properties of the tailed bacteriophage l3 to acholeplasma laidlawii cells were studied. adsorption followed a biphasic curve. reversibility and virus heterogeneity were not sufficient to explain the break in the adsorption curve. binding studies showed that each colony-forming unit could bind about 350 virions. the electrostatic nature of l3 adsorption was indicated by the effect of cations, ph, and temperature on the adsorption rate constant. l3 adsorption appeared to have a requ ... | 1982 | 7042999 |
| canine mycoplasmas: their ecologic niche and role in disease. | | 1982 | 7045054 |
| the use of differential scanning calorimetry and differential thermal analysis in studies of model and biological membranes. | differential scanning calorimetry (dsc), and to a lesser extent differential thermal analysis (dta), are powerful yet relatively rapid and inexpensive thermodynamic techniques for studying the thermotropic phase behavior of lipids in model and biological membranes, without the introduction of exogenous probe molecules. in this review the principles as well as the scope and limitations of dsc and dta are discussed first. the application of these techniques to the study of the thermotropic phase b ... | 1982 | 7046969 |
| immunological and functional activity of spleen lymphocytes from mice infected by acholeplasma laidlawii cells and rauscher virus. | the duration of acholeplasma laidlawii antigen persistence in mice, resistant to rausher leukemia virus, after infection with both a. laidlawii cells and rausher virus has been studied. the antigen persistence was accompanied by marked depression of immune response which was especially severe in case of mixed acholeplasmavirus infection. such immunosuppression and observed infiltration of the spleen with immature leukemic cells can be regarded as a preleukosis. immunosuppression was accompanied ... | 1982 | 7048811 |
| viruses of mycoplasmas and spiroplasmas. | acholeplasmas, mycoplasmas and spiroplasmas of the class mollicutes have been shown to carry dna viruses. morphologically they occur as rods, polyhedrons with short or long tails and as enveloped spheres. these latter resemble enveloped nonlytic animal viruses and are now placed in the new family of bacterial viruses the plasmaviridae. viruses of mycoplasmas and spiroplasmas present a suitable experimental model for studies of the virus-cell interactions. | 1982 | 7050553 |
| isolation of acholeplasma laidlawii from a giraffe (giraffa camelopardalis rothschildi) and a mouflon (ovis musimon). | | 1982 | 7064318 |
| comparison of ciliostasis by mycoplasmas in mouse and chicken tracheal organ cultures. | the cilia-stopping effect of mycoplasmas of human and various animal origin in mouse and chicken tracheal organ cultures was studied. from the results in mouse tracheal organ cultures, the mycoplasma strains tested were divided into three groups: mycoplasma pulmonis m53, m pulmonis jb, m. pulmonis ok, m. mycoides subsp. mycoides pgl and m. gallisepticum s6 showed a strong cilia-stopping effect; m. pulmonis pg22, m. mycoides subsp. capri pg3, m. meleagridis 19729, m. neurolyticum type a and m. ar ... | 1982 | 7087799 |
| effects of cholesterol on the orientational order of unsaturated lipids in the membranes of acholeplasma laidlawii. a 2h-nmr study. | we have investigated by 2h-nmr the effects of the incorporation of cholesterol on the orientational order of unsaturated lipid acyl chains in the membranes of acholeplasma laidlawii b. this is the only 2h-nmr study to date of the influence of cholesterol in a biological membrane using specifically labelled fatty acids. we observed the characteristic condensing effect of cholesterol on the lipid acyl chain order in the liquid crystalline phase. in terms of the percentage increase in the quadrupol ... | 1982 | 7093275 |
| isolation and identification of mycoplasmas from the respiratory tract of the white leghorn chicken in the sudan. | | 1982 | 7093655 |
| isolation and preliminary characterisation of mycoplasmavirus 20-p. | a mycoplasmavirus, mv 20-p, was isolated from the fastidious, slow-growing human mycoplasma 20-p, previously identified by the growth inhibition test as mycoplasma hominis type 2. its broth culture was ultracentrifuged into 35% saccharose, the pellet was resuspensed in buffer, and the suspension was dropped onto laws of the virus indicator acholeplasma laidlawii bcl-13. the virus was washed off the plaque areas by buffer. mv 20-p appeared in electron microscopy as spherical, enveloped particles ... | 1982 | 7098542 |
| a 2h-nmr study of acholeplasma laidlawii membranes highly enriched in myristic acid. | myristic acid specifically deuterated at several positions along the acyl chain was biosynthetically incorporated into the membrane lipids of acholeplasma laidlawii b to the level of greater than or equal to 90%. 2h-nmr was used to study the molecular order and lipid phase composition of the membranes as a function of temperature. isolated membranes and intact cells give rise to similar 2h spectra. below 25 degrees c the spectra exhibit a broad gel phase component which at 0 degrees c reaches th ... | 1982 | 7104342 |
| identification of iron- and phosphorus-containing antigens of the acholeplasma laidlawii cell membrane. | | 1982 | 7106296 |
| serological investigation of horse sera for antibodies against mycoplasmas and acholeplasmas. | sera from horses with respiratory disease (rd) have been investigated using the complement fixation test, indirect hemagglutination test, enzyme immune assay, and the metabolic inhibition test, and sera from mares after abortion, using the complement fixation test, indirect hemagglutination test and enzyme immune assay, for antibodies against mycoplasma equirhinis, m subdolum, m. equigenitalium, m. pulmonis, m. felis, acholeplasma laidlawii, a. hippikon and a. equifetale. antibodies were found a ... | 1982 | 7112894 |
| isolation of acholeplasmas from horse feces. | acholeplasmas were detected in five of 96 feces samples from clinically normal horses. three of the five strains isolated were identified as a. equifetale, one as a. hippikon, and one was serologically identical with the acholeplasma strain 881. | 1982 | 7112898 |
| virus capping on mycoplasma cells and its effect on membrane structure. | the capping of mycoplasmavirus l3 on the surface of acholeplasma laidlawii was investigated. in electron microscope studies we observed a reduced capping after treatment of the host cell with energy-blocking agents. other drugs inhibiting ligand capping on eucariotic cells had no effect. changes in membrane structure after virus adsorption were observed spectroscopically using the excimer fluorescence technique. the results are interpreted in terms of a lipid-protein phase separation in connecti ... | 1982 | 7115700 |
| lateral mobility of membrane-bound antibodies on the surface of acholeplasma laidlawii: evidence for virus-induced cell fusion in a procaryote. | dynamic processes on the membrane of the procaryotic cell acholeplasma laidlawii have been studied by means of immunoelectron microscopy. colloidal gold-labeled anti-a. laidlawii antibodies were used as electron-dense markers. this method allowed the demonstration of temperature-dependent lateral mobility of membrane-bound immunoglobulins. by using two different sizes of gold grains to differentiate cells from two different cell populations, virus-induced fusion of procaryotic cells could be sho ... | 1982 | 7118831 |
| active diffusion of adsorbed mycoplasmal virus l3 on acholeplasma laidlawii cell membranes. | | 1982 | 7123047 |
| lipid phase structure in the regulation of lipid composition in acholeplasma laidlawii membranes. | in acholeplasma laidlawii membranes the ratio between the dominating lipids, monoglucosyldiglyceride (mgdg) and diglucosyldiglyceride (dgdg), depends on temperature, configuration of incorporated fatty acids, and membrane cholesterol content, which affect the molecular geometry of the lipids. mgdg and dgdg have wedge- and rod-like molecular shapes, respectively, that are modifiable. the packing constraints of lipids in amphiphilic aggregates, i.e., the area of the hydrocarbon-water interface and ... | 1982 | 7123057 |
| the electrochemical potential across mycoplasmal membranes. | the electrochemical proton gradient across mycoplasmal membranes was studied. the transmembrane proton-motive potential, delta p, is composed of two parameters, a transmembrane electric potential difference, delta psi, and a transmembrane proton gradient, delta ph, according to the formula delta p = delta psi -(a x delta ph). membrane potentials were determined with use of potential-sensitive cyanine dyes. the delta psi for both mycoplasma mycoides subspecies capri and mycoplasma gallisepticum w ... | 1982 | 7123058 |
| [simultaneous isolation of infected and non-infected clones of mycoplasmas from plaques obtained on acholeplasma laidlawii lawns with a virus of group l1 of gourlay]. | | 1982 | 7124157 |
| tylosin tartrate and tiamutilin effects on experimental piglet pneumonia induced with pneumonic pig lung homogenate containing mycoplasmas, bacteria and viruses. | the effects of tylosin tartrate and tiamutilin were examined in pneumonias induced experimentally in neonatal piglets with a homogenate of pneumonic pig lung, obtained from pigs with naturally acquired enzootic pneumonia. the homogenate contained mycoplasmas, including mycoplasma hyopneumoniae (m suipneumoniae) and m hyorhinis, and certain bacteria and viruses. the experimental pneumonias generally resembled mycoplasmal pneumonia histologically but were complicated by aspiration pneumonia in som ... | 1982 | 7134653 |
| isolation of acholeplasma oculi from genital lesions in sheep. | | 1982 | 7147669 |
| preferential uptake of lipids by mycoplasma membranes from human plasma low-density lipoproteins. | the binding and transfer of low-density lipoprotein (ldl) constituents to mycoplasma membranes were examined. mycoplasma capricolum was found to bind more 125i-labeled ldl than acholeplasma laidlawii. free and esterified cholesterol uptake was 3-4 times higher in m. capricolum than in a. laidlawii. cholesterol transfer to the membranes of both organisms far exceeded the amounts of cholesterol expected according to ldl protein found associated with the membranes. trypsin digestion of the membrane ... | 1982 | 7150569 |
| [proteins of bacterial membranes. nadh-dehydrogenase from the cells of acholeplasma laidlawii]. | using ion-exchange chromatography on deae-cellulose and gel filtration, a purified nadh-dehydrogenase was prepared from cell membranes of a. laidlawii. the enzyme specific activity exceeds the activity of the membrane preparation 45-fold. the enzyme is thermolabile and sensitive to lecithine. electrophoresis of the enzyme preparation in the presence of na-ds resulted in two proteins with mr of 65 000 and 72 000. specific staining of the gels with triphenyltetrasolium chloride in the presence of ... | 1982 | 7150675 |
| comparison of the ultrastructural aspects of acholeplasma laidlawii grown in liquid and solid media. | | 1982 | 7159213 |
| isolation of mycoplasmas from experimental ferrets (mustela putorius). | a total of 21 apparently healthy experimental ferrets, 8 males and 13 females, comprizing 1, 2 and 3 year-old animals were examined for mycoplasmatales. mycoplasmas were isolated from 17 samples of 21 oral cavities (81.0%), and from 2 of 21 nasal cavities (9.5%), but not from the prepuce or vagina of the animals. neither ureaplasma nor acholeplasma was demonstrated in any of the locations of the ferrets examined. these mycoplasma strains proved to metabolize glucose but not arginine and urea. th ... | 1982 | 7169088 |
| replication of mycoplasma virus l51. vii. effect of chloramphenicol on the synthesis of dna replicative intermediates. | chloramphenicol affects several steps in the dna replication of mycoplasma virus l51, a noncytocidal, naked, bullet-shaped virion containing circular single-stranded (ss) dna of 1.5 x 10(6) daltons (4.5 kilobases). in the presence of chloramphenicol, adsorption was normal and parental ss dna was converted to double-stranded replicative forms (rf), but subsequent rf leads to rf replication was inhibited. chloramphenicol added late in infection, when most viral nascent dna is in progeny ss molecul ... | 1982 | 7176020 |
| antibiotic sensitivities of mycoplasmas. | | 1982 | 7179710 |
| prevalence of mycoplasma and chlamydia in the nasal flora of dairy calves. | nasal swabs from dairy calves in 20 selected herds were collected once in each of three sampling periods in one year and cultured for mycoplasmas and chlamydiae. seventy-seven of 411 calves (19%) and 16 of 20 herds (80%) were positive for mycoplasmas at least once throughout the year, and all of 378 calves sampled from the 20 herds were negative for chlamydiae. thirty-one percent of the isolates were mycoplasma bovirhinis; other species isolated less frequently were mycoplasma bovis, mycoplasma ... | 1982 | 7179720 |
| effect of molecular weight of polyethylene glycols on inactivation of mycoplasma pulmonis and acholeplasma laidlawii a. | | 1982 | 7186082 |
| growth medium constituents contaminating mycoplasma preparations and their role in the study of membrane glycoproteins in porcine mycoplasmas. | several mycoplasma and acholeplasma species chosen at random and solubilized with sodium dodecyl sulphate showed a common periodic acid-schiff positive band with an apparent molecular weight of about 64 000, when examined by polyacrylamide gel electrophoresis. another more cathodic minor band was detected in m. hyopneumoniae and m. flocculare. the common periodic acid-schiff positive band appeared when a precipitate of serum constituents of the uninoculated growth medium after incubation was exa ... | 1980 | 7190998 |
| isolation of mycoplasma from a buffalo (bubalus bubalis) with mastitis. | | 1981 | 7199239 |
| reversed cubic phase with membrane glucolipids from acholeplasma laidlawii. 1h, 2h, and diffusion nuclear magnetic resonance measurements. | monoglucosyl diglyceride and diglucosyl diglyceride are the dominant lipids of the acholeplasma laidlawii membrane. diglucosyl diglyceride forms a lamellar liquid crystalline phase with water while monoglucosyl diglyceride forms a reversed hexagonal phase. depending on the amounts of unsaturated acyl chains of the lipids, a mixture of monoglucosyl diglyceride and diglucosyl diglyceride forms lamellar or reversed cubic phases at physiological temperatures. a high degree of cis unsaturation favors ... | 1981 | 7213607 |
| lipid and protein membrane components associated with cholesterol uptake by mycoplasmas. | membranes of mycoplasma species take up 2--4 times more exogenous cholesterol than membranes of acholeplasma species. to test whether the lower cholesterol uptake capacity of acholeplasma is due to the high glycolipid content of their membranes, the phospholipids of acholeplasma laidlawii and mycoplasma capricolum membranes were hydrolyzed by phospholipase a2. digestion removed about 30% of the polar lipids of a. laidlawii, leaving the glycolipids and phospholglycolipids intact, and about 70% of ... | 1981 | 7213725 |
| effects of charged cholesteryl esters on mycoplasma growth. | | 1980 | 7215545 |
| analysis of multiple isoenzyme expression among twenty-two species of mycoplasma and acholeplasma. | crude extracts of triple-cloned, purified cultures of 22 species of mycoplasma and acholeplasma were examined for expression of 21 isozyme systems routinely used to type mammalian cells. nine previously described enzymes (purine nucleoside phosphorylase, adenylate kinase, dipeptidase, esterase, glyceraldehyde-3-phosphate dehydrogenase, glucose phosphate isomerase, glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, and superoxide dismutase) and three enzymes not previously repor ... | 1981 | 7217001 |
| first observation of amino acid side chain dynamics in membrane proteins using high field deuterium nuclear magnetic resonance spectroscopy. | we have obtained the first deuterium nmr spectra of an individual membrane protein, bacteriorhodopsin in the purple membrane of halobacterium halobium r1. biosynthetic isotopic enrichment with [gamma-2h6]valine and high field fourier transform operation permitted rapid data acquisition on intact membranes, including measurement of relaxation times. at some temperatures high quality spectra could be obtained in less than 1 s. [u-14c]valine tracer studies indicate that less than or equal to 2% of ... | 1981 | 7217074 |
| the growth precipitation test as a diagnostic method for differentiation of mycoplasma and acholeplasma species. | | 1980 | 7223574 |
| [cilia-inhibiting activity of different mycoplasma hyorhinis strains compared to acholeplasma and other mycoplasma species in tracheal organ cultures]. | | 1981 | 7234234 |
| adenylate energy charge in acholeplasma laidlawii. | adenosine 5'-triphosphate, adenosine 5'-diphosphate, and adenosine 5'-monophosphate were produced by acholeplasma laidlawii b-pg9 growing in modified edward medium. the adenylate energy charge was calculated to be 0.84 +/- 0.07 and ranged from 0.91 to 0.78 during exponential growth (12 to 24 h). during exponential growth, a. laidlawii contained, at 17.5 h, 2.3 x 10(-17) mol of adenosine 5'-triphosphate per colony-forming unit and, at 16 h, 27.3 nmol of adenosine 5'-triphosphate per mg (dry weigh ... | 1981 | 7240083 |
| respiration-associated components of mollicutes. | no cytochrome pigments were detected by difference (reduced minus oxidized) spectroscopy at liquid nitrogen temperature in whole-cell preparations or membrane fractions of acholeplasma axanthum s273, acholeplasma equifetale n93, acholeplasma granularum bts39, acholeplasma laidlawii b-pg9, acholeplasma modicum pg-49, acholeplasma oculi 19l, mycoplasma arginini g230, mycoplasma arthritidis 07, mycoplasma pneumoniae fh, and mycoplasma pulmonis jb. all ten mollicutes species examined contained iron ... | 1981 | 7240087 |
| the effect of cholesterol on the phase structure of glucolipids from acholeplasma laidlawii membranes. | 1. the packing properties in lipid mixtures containing cholesterol and membrane glucolipids from acholeplasma laidlawii are modified by varying the amounts of cholesterol, diacylmonoglucosylglycerol and diacyldiglucosylglycerol in the mixtures as well as the temperature and the degree of acyl chain unsaturation. these changes affect both the proportions of different lipids having dissimilar molecular geometries and the geometry of the lipid molecules themselves. 2. all mixtures containing glucol ... | 1981 | 7250125 |
| isolation and identification of mycoplasmas from pig lungs in singapore. | a total of 656 lung specimens comprising 196 grossly pneumonic lungs from clinically diseased pigs and 230 grossly pneumonic and normal lungs from abattoirs were cultured for mycoplasmas. mycoplasmas or acholeplasmas were recovered from 102 lung specimens, of which 28 were serologically identified (by disc growth inhibition and agar gel diffusion tests) as mycoplasma suipneumonia, 14 as m hyorhinis, 35 as acholeplasma granularum and 4 as a laidlawii. in addition, 15 isolates were unclassified an ... | 1981 | 7257151 |
| studies on acholeplasma laidlawii grown on branched-chain fatty acids. | | 1981 | 7259182 |
| effects of anesthetics on water permeability and lipid metabolism in acholeplasma laidlawii membranes. | the addition of tetracaine and diethyl ether to acholeplasma laidlawii at concentrations commonly used for local anesthesia did not affect water permeability over the cell membrane, as measured by a pulsed magnetic field gradient nmr method. however, a. laidlawii changed its membrane lipid composition upon treatment with these anesthetics. both tetracaine and diethyl ether addition resulted in a decrease in the molar ratio between the major membrane glucolipids, monoglucosyldiacylglycerol and di ... | 1981 | 7260084 |
| cytoplasmic helical structure associated with acholeplasma laidlawii. | a distinct spiral protein structure was found in three species of acholeplasma, but was not found in the mycoplasma species studied. the spirals, which are 14 nm in width and of variable length from 50 to 300 nm, are formed by a helical arrangement of 7-nm subunits. a rosette-like structure 45 nm in diameter also composed of 7-nm subunits was found in close association with the spirals and may be a taut in vivo form of the spiral. the electrophoretic profile in sodium dodecyl sulfate-polyacrylam ... | 1981 | 7263616 |
| partial nucleotide sequence similarity within species of mycoplasma and acholeplasma. | the nucleotide sequence relationships between 18 species of mycoplasma and 3 species of acholeplasma were examined by solution dna hybridization. radiolabeled dnas from strains representing 13 mycoplasma and 2 acholeplasma species were used as hybridization probes. the mycoplasmas were heterogeneous but displayed a low degree of conserved information of the order of 3 to 5% of the genome. however, several species within each genus showed 13 to 15% homology. there was no detectable homology betwe ... | 1980 | 7264601 |
| detection of mycoplasmal contaminants in sera. | | 1981 | 7275992 |
| isolation and characterization of mycoplasma and acholeplasma from apparently healthy and diseased (infectious sinusitis) turkeys. | investigation of 136 turkeys (24 manifesting infra-orbital sinusitis, 112 apparently healthy) resulted in isolation of 79 strains of mycoplasma and 4 of acholeplasma. by the disc growth inhibition test with 16 reference antisera of avian serogroups, 55 strains were identified serologically and 28 remained unidentified. thirteen strains of mycoplasma gallisepticum, 1 of m. meleagridis, and 2 of acholeplasma laidlawii were isolated from turkey sinusitis whereas serogroups c (2), d (19), f (8), m. ... | 1981 | 7278710 |
| structure of the oligosaccharide chain of lipoglycan from acholeplasma granularum. | the membrane associated lipoglycan from acholeplasma granularum is a linear oligosaccharide attached to a diacylglycerol. the polymer has a monomeric weight of 20000 and is composed of glucose, galactose, n-acetylglucosamine, n-acetylfucosamine, glycerol and fatty acid esters. the proposed structure of the oligosaccharide chain is 12 repeating units of 9 sugars: glcp(beta 1 leads to 2)-glcp(alpha 1 leads to 4)-glcp(alpha 1 leads to 3,4)-fcnac(beta 1 leads to 3)-galp(alpha 1 leads to 3)-galp(alph ... | 1981 | 7284419 |
| membrane structures of acholeplasma laidlawii and its virus. | the main types of ultrastructures found in the freeze-fracture faces of acholeplasma laidlawii s 2 and its virus mv-lg-l 172 were (1) particles 7-19 nm in diameter, mostly located in the convex cytoplasmic fracture faces. (2) small bulges or aggregates, 13-25 nm in diameter, which occupied only limited areas of both inner and outer fracture faces of some mycoplasmas, (3) numerous tiny grains and/or spikes 2-6 nm in diameter, protruding from a finely structured background, especially in the outer ... | 1981 | 7286852 |
| mycoplasma-virus contacts, budding and scars remaining in the membranes of acholeplasma laidlawii and its virus. | various stages of virus and mycoplasma budding indicated that both virus and, most probably some mycoplasma progeny developed by budding. besides this alternative, binary fission was the mode of mycoplasma reproduction. mycoplasma-virus and mycoplasma-mycoplasma connections by stems were observed. circular scars, 40-80 nm in diameter, often in groups, were left in the membrane of mycoplasmas by the budding bodies. cytoplasmic structures seen in cross-fraction are presented. a relatively small nu ... | 1981 | 7286853 |
| mycoplasma infections of plants. | plants can be infected by two types of wall-less procaryotes, spiroplasmas and mycoplasma-like organisms (mlo), both located intracellularly in the phloem tissues of affected plants. spiroplasmas have been cultured, characterized and shown to be true members of the class mollicutes. mlo have not yet been cultured or characterized; they are thought to be mycoplasma-like on the basis of their ultrastructure as seen in situ, their sensitivity to tetracycline and resistance to penicillin. mycoplasma ... | 1981 | 7287398 |
| cholesterol transfer from normal and atherogenic low density lipoproteins to mycoplasma membranes. | the purpose of this study was to determine whether the free cholesterol of hypercholesterolemic low density lipoprotein from cholesterol-fed nonhuman primates has a greater potential for surface transfer to cell membranes than does the free cholesterol of normal low density lipoprotein. the low density lipoproteins were isolated from normal and hypercholesterolemic rhesus and cynomolgus monkeys, incubated with membranes from acholeplasma laidlawii, a mycoplasma species devoid of cholesterol in i ... | 1981 | 7295188 |
| protein composition and extractability of lipid-modified membranes from acholeplasma laidlawii. | membranes from acholeplasma laidlawii have been extracted with neutral detergents, which solubilize the proteins and lipids selectively, or with sodium deoxycholate, which gives an almost total solubilization. the amounts of individual proteins present in the detergent extracts of membranes with induced variations in lipid compositions were determined by crossed immunoelectrophoresis. extraction with the neutral detergent tween 20 showed that ionic lipids and the glucolipid diglucosyl diglycerid ... | 1981 | 7306495 |
| purification and characterization of nadh oxidase from membranes of acholeplasma laidlawii, a copper-containing iron-sulfur flavoprotein. | 1. nadh oxidase was extracted from the membranes of acholeplasma laidlawii with buffer containing 3% triton x-100 and subsequently purified by several chromatographic steps. the final preparation was essentially homogeneous as judged by gel electrophoresis under nondenaturing conditions. 2. the enzyme appears to be a copper-containing iron-sulfur flavoprotein (fmn:cu:fe:labile s = 1:1:6:6). the enzyme, containing a high fraction of hydrophobic amino acids, is composed of three subunits of molecu ... | 1981 | 7318830 |
| isolation of acholeplasma oculi in northern ireland. | | 1981 | 7336542 |
| bovine genital mycoplasmosis. | infection, lesions and clinical significance of acheloplasmas, mycoplasma bovis and mycoplasma bovigenitalium in genital disease of cattle are described. a more detailed account is given of ureaplasma infections. acute and chronic forms of granular vulvitis in both field and experimental disease are described as well as the role of the organism in abortion. recovery rates of ureaplasma and mycoplasma from semen and preputial washings in bulls are outlined and their significance in disease is dis ... | 1981 | 7337908 |
| distribution of ureaplasmas in the urogenital tract of ewes. | | 1981 | 7344258 |
| [serodiagnosis of mycoplasma infections in swine]. | | 1981 | 7347583 |
| control of membrane polar lipid composition in acholeplasma laidlawii a by the extent of saturated fatty acid synthesis. | the low level of endogenous fatty acid synthesis in acholeplasma laidlawii a strain ef22 was found to be caused by a deficiency of pantetheine in the lipid-depleted growth medium. by supplementing the oleic acid-containing medium with increasing concentrations of pantethein, saturated fatty acid synthesis was stimulated (having an apparent km of 5 microm for pantetheine) and the incorporation of endogenously synthesized fatty acids in membrane lipids increased markedly. furthermore, carotenoid b ... | 1980 | 7352994 |
| lipid chain order in acholeplasma laidlawii membranes. what does 2h nmr tell us? | | 1980 | 7353632 |
| the isolation of acholeplasma oculi from an outbreak of ovine keratoconjunctivitis. | | 1980 | 7355555 |
| serological studies of bovine ureaplasmas by agar-gel precipitation test. | | 1980 | 7366058 |
| lipid and protein composition and thermotropic lipid phase transitions in fatty acid-homogeneous membranes of acholeplasma laidlawii b. | the membrane composition and lipid physical properties have been systematically investigated as a function of fatty acid composition for a series of acholeplasma laidlawii b membrane preparations made homogeneous in various fatty acids by growing cells on single fatty acids and avidin, a potent fatty acid synthetic inhibitor. the membrane protein molecular weight distribution is essentially constant as a function of fatty acid composition, but the lipid/protein ratio varies over a 2-fold range w ... | 1980 | 7370250 |
| an aldehydophosphoglycolipid from acholeplasma granularum. | a novel phosphoglycolipid and a triglucosyl diacylglycerol were found among the lipids of acholeplasma granularum. the tentative structure of the phosphoglycolipid was determined to be a phosphotriester, [beta-d-glucopyranosyl-(1 leads to 1)-x-glycerol-3-o-] [d-glyceraldehyde-3-o-] [1,2-diacyl-x-glycerol-3-o-kojibiosyl-6-o-]phosphate. the structure assigned to the triglucosyl lipid was beta-d-glucopyranosyl-(1 leads to 3)-alpha-d-glucopyranosyl-(1 leads to 2)-alpha-d-glucopyranosyl-(1 leads to 1 ... | 1980 | 7370288 |
| inactivation of mycoplasma in serum with binary ethyleneimine. | a method of inactivating mycoplasma contaminants in sera by using binary ethyleneimine was tried. when used at the concentration recommended for inactivating viruses, 0.001 m, binary ethyleneimine inactivated only two of five mycoplasma species. even at a concentration of 0.01 m, the compound did not consistently inactivate all mycoplasmas. | 1980 | 7372800 |
| colony morphology, ultrastructure and morphogenesis in mycoplasma hominis, acholeplasma laidlawii and ureaplasma urealyticum. | colonies of mycoplasma hominis, acholeplasma laidlawii (three strains) and ureaplasma urealyticum were examined by light and electron microscopy and their characteristic morphology, ultrastructure and morphogenesis are described. mycoplasma hominis and a. laidlawii, pg8 and oral strains, developed typical 'fried-egg' colonies which were remarkably heterogeneous in size. the colonies of a. laidlawii strain nctc 10116 were more homogeneous and grew mainly on the surface of the agar showing a fine ... | 1980 | 7373281 |
| ultrastructural study of the interaction between acholeplasma laidlawii and antibody. | the ultrastructure of agar-grown acholeplasma laidlawii incubated with specific antiserum or igm fractions of this antiserum has been investigated by the thin-sectioning technique. antiserum treatment resulted in the development of giant cells along the colony circumferences and in the coating of normal-size mycoplasmas with a periodically arranged extramembranous layer, consisting of attached immunoglobulins as shown by indirect immunoferritin labelling. the regular structure of the coat was no ... | 1980 | 7373282 |
| a survey of mycoplasma infections in domestic poultry. | a survey of mycoplasma infections of chickens, turkeys and ducks was made on tissues from a variety of sources and birds of various ages, and from pipped and dead-in-shell turkey embryos. the tissues examined consisted mainly of respiratory tissue and the cloaca and contents and also a small number of joint lesions and other tissues. from chickens, mycoplasmas were isolated from a total of 138 tissues with mycoplasma gallisepticum in preponderance. this was followed by m gallinarum, untyped orga ... | 1980 | 7375739 |
| phospholipid and cholesterol uptake by mycoplasma cells and membranes. | the ability of growing mycoplasma cells and their isolated membranes to take up exogenous phospholipids was correlated with their ability to take up cholesterol. horse serum or vesicles made of phosphatidylcholine and cholesterol served as lipid donors. growing cells of five mycoplasma species took up significant quantities of phosphatidylcholine and sphingomyelin as well as free and esterified cholesterol. in contrast, growing cells of three acholeplasma species failed to take up any of the exo ... | 1980 | 7388026 |
| isoenzymes in two species of acholeplasma. | the reference strains type a and type b and two equine strains of acholeplasma laidlawii were examined for a wide range of isoenzymes using thin-layer starch-gel electrophoresis; in addition two isoenzymes were examined in two strains of a. equifetale. the type strains a and b of a. laidlawii were differentiated by their lactate dehydrogenase, phosphoglucomutase and aspartate aminotransferase patterns and the two equine strains by their hexokinase, lactate dehydrogenase and phosphoglycerate kina ... | 1980 | 7391817 |
| lipid bilayer stability in membranes. regulation of lipid composition in acholeplasma laidlawii as governed by molecular shape. | the polar lipid composition in membranes of acholeplasma laidlawii is extensively regulated as a response to environmental changes. in particular, the ratio between the dominating lipids monoglucosyldiglyceride and diglucosyldiglyceride is altered depending on temperature, configuration of incorporated fatty acids, and membrane cholesterol content. synthesis of monoglucosyldiglyceride is stimulated by low temperature and saturated fatty acids but diminished by the presence of cholesterol. these ... | 1980 | 7407064 |
| orientational order of unsaturated lipids in the membranes of acholeplasma laidlawii as observed by 2h-nmr. | oleic acid specifically deuterated at fifteen different positions along the chain, including the double bond, was biosynthetically incorporated into the membrane lipids of the microorganism acholeplasma laidlawii b. a detailed study of the dynamic conformation of these chains was carried out using deuterium nuclear magnetic resonance. the deuterium spectra fourteen different samples were recorded as a function of temperature over the range 0-41 degrees c. spectra were obtained down to -52 degree ... | 1980 | 7407113 |
| the influence of the fatty acid composition of acholeplasma laidlawii membranes on the growth inhibitory activity of narasin, a polyether ionophorous antibiotic. | narasin, apolyether ionophorous antibiotic capable of acting as a transmembrane carrier of cations, has a growth inhibitory effect on acholeplasma laidlawii, permitting only 20% survival when present as 0.1 micrograms/ml in an undefined growth nutrient or fatty acid-deficient nutrient supplemented only with palmitic acid. when a. laidlawii is propagated in fatty acid-deficient nutrient supplemented with linoleic acid, however, the organisms become 40 times more sensitive to the growth inhibitory ... | 1980 | 7407129 |
| [blast transformation in response to plant mitogens in wistar rats infected with mycoplasma arthritidis or acholeplasma laidlawii]. | the response of lymphocytes of m. arthritidis- or a. laidlawii-infected rats to pha and cona was studied. mycoplasma infection was shown to stimulate the dna synthesis in lymphocytes of the spleen and lymph nodes and to depress the responses to mitogenes one week after infection. by the same time splenocytes of a. laidlawii-infected rats were shown to only slightly proliferate in response to pha. after 4 weeks of infection the lymphocyte transformation was greatly increased in both mycoplasma- a ... | 1980 | 7407377 |
| [chronic infection of acholeplasma laidlawii by a group l 1 mycoplasma virus]. | mycoplasma virus mvl 51, of the group l1 of gourlay, has been shown to induce a chronic cell infection of two reference strains (1305/68 and ja 1) of acholeplasma laidlawii. titers of virus and cells remain at a fairly high level during infection, around 10(8) units/ml, with a mean ratio of approximately 1 pfu/1 cfu, as under control of a regulation mechanism. however, sudden spontaneous variations in the virus level do occur, from time to time, thus suggesting transient regulation breaks but no ... | 1980 | 7407696 |
| membrane composition and virus susceptibility of acholeplasma laidlawii. | the membrane composition of 11 strains of acholeplasma laidlawii, including three strains persistently infected with mycoplasmaviruses mvl51, mvl2, and mvl3, was studied and correlated with mycoplasmavirus sensitivity. membranes of the strains had similiar sodium dodecyl sulfate-polyacrylamide gel electrophoresis patterns, and all strains were inhibited by an antiserum produced against membranes from one of the strains. the amounts of integral membrane proteins solubilized by the nonionic deterg ... | 1980 | 7410317 |
| aminopeptidase activity of acholeplasma laidlawii, mycoplasma bovirhinis, mycoplasma dispar and mycoplasma bovis. | aminopeptidase activity was demonstrated in extracts of acholeplasma laidlawii, mycoplasma bovirhinis, m. bovis and m. dispar. the enzyme specificity, which differed amongst the mycoplasma species examined, was characterized using 19 aminoacyl-beta-naphthylamides as substrates. the differences were detected after 4 h incubation with the substrates and potentially could be employed to aid in the characterization of certain mycoplasma species. | 1980 | 7411115 |
| virus and host cell dna syntheses during infection of acholeplasma laidlawii by mvl3, a nonlytic cytocidal mycoplasmavirus. | the replication of mycoplasmavirus mvl3 in acholeplasma laidlawii k2 host cells was studied by analysis of infected-cell lysates using sedimentation in sucrose gradients and dna-dna hybridization. viral dna replication was found to involve intermediates sedimenting faster than free viral dna, which is a linear, double-stranded molecule of about 26 x 10(6) daltons. after the shutdown of cellular dna synthesis, viral dna synthesis continued for many hours. the fate of cellular and parental viral d ... | 1980 | 7411689 |
| examination of uterine biopsies from infertile cows for the presence of viruses and mycoplasmas. | uterine biopsies from 45 infertile cows were examined for the presence of mycoplasmas, bovine viral diarhoea--mucosal disease virus, bovine syncytial virus and other viruses. no viruses were detected. ureaplasmas were isolated from four cows, two clinically normal and two with nodular vulvovaginitis. | 1980 | 7414068 |
| effect of cell membrane composition on the growth and composition of a nonlytic enveloped mycoplasmavirus. | | 1980 | 7414958 |
| [stimulation of hematopoiesis in mice inoculated with mycoplasma arthritidis]. | m. arthritidis is known to enhance the leukemogenic effect of rauscher leukemia virus in mice of different strains. as we have found earlier, m. arthritidis enhanced endogenous colony formation in irradiated mice. in this paper we made an attempt to establish a connection between these two phenomena. the mixed inoculation of balb/c mice with m. arthritidis and rauscher leukemia virus produced a great increase in the number of endogenous colonies as compared with the effect of mycoplasmas alone, ... | 1980 | 7415681 |
| ultraviolet, photodynamic and thermal inactivation of mycoplasmaviruses. | the ultraviolet light, photodynamic, and thermal inactivation parameters have been measured for the three groups of mycoplasmaviruses. the differences in these parameters for the three virus groups reflect differences in virion structure and in genome size and structure. | 1980 | 7421606 |
| endotoxin-like activities of mycoplasmal lipopolysaccharides (lipoglycans). | lipoglycans (previously designated lipopolysaccharides) from several species of acholeplasma and from thermoplasma acidophilum were examined for endotoxin-like activities as measured by the standard rabbit fever test and the limulus amoebocyte lysate assay. the lipoglycans from acholeplasma granularum, achloplasma laidlawii, acholeplasma modicum, and acholeplasma oculi caused a febrile response at concentrations of 1 ng/ml per kg or greater, whereas with control escherichia coli ec-2 lipopolysac ... | 1980 | 7429642 |
| methylated bases in mycoplasmal dna. | the dnas of four mycoplasma and one acholeplasma species were found to contain methylated bases. all of the five species contained 6-methyladenine (m6ade), the methylated base characteristic of prokaryotic dna. the extent of methylation of adenine residues in the mycoplasmal dna ranged from 0.2% in mycoplasma capricolum to about 2% in mycoplasma arginini and mycoplasma hyorhinis with intermediate methylation values for mycoplasma orale and acholeplasma laidlawii dnas. about 5.8% of the cytosine ... | 1980 | 7433124 |
| interaction of mycoplasma virus type 2 with cellular components of acholeplasma laidlawii strain ja1. | mycoplasma virus type 2 was shown to adsorb specifically to intact cells, membranes, and lipoglycan of acholeplasma laidlawii strain ja1 but not to these components of acholeplasma oculi. the oligosaccharide chain of the lipoglycan defined the specificity of the receptor site since deacylation not only did not reduce adsorption but increased it threefold. actual adsorption of virus to lipoglycan was demonstrated by sucrose density gradient separation of the virus-lipoglycan complex. a strain of ... | 1980 | 7441818 |
| adsorption, capping, and release of a complex bacteriophage by mycoplasma cells. | by electron microscopic studies, the adsorption and release of nonlytic, cytocidal mycoplasma virus mvl3, which infects acholeplasma laidlawii cells, have been examined. the mvl3 virion has a polyhedral head, collar, short tail, and tail fibers and contains linear double-stranded dna. adsorbed mvl3 virus showed a temperature-dependent clustering or capping on the mycoplasma cell membrane. during infection, a number of virus-cell membrane-related structures were observed, suggesting a general mod ... | 1980 | 7441822 |
| [stimulation of erythropoiesis in mice with mycoplasma infections]. | mycoplasma arthritidis was shown earlier to induce erythropoietin-independent erythropoiesis in infected mice. this study demonstrated the increased 59fe incorporation in the mouse spleen as early as day 4 after infection with m. arthritidis. it is known that inoculation of mice with low doses of actinomycin d (act d) results in a specific suppression of erythropoiesis without impairing the endogenous erythropoietin production. in this study the mice were injected with act d (80 microgram/kg bod ... | 1980 | 7448391 |
| giant cell formation in acholeplasma laidlawii, strain ja1. | striking alterations, which looked like blebs, were observed in colonies of acholeplasma laidlawii, strain ja 1. "craters" were seen on the surface of these colonies by scanning electron microscopy. in addition, giant cells of acholeplasma, up to 14 microns in diameter, i.e. approximately 20 times the size of a normal a. laidlawii cell, were visible in the colonies. the large forms were surrounded by a unit membrane. after infection with group 1 and group 2 mycoplasma-viruses, the proportion of ... | 1980 | 7467914 |
| influence of monoglucosyldiacylglycerol and monoacylmonoglucosyldiacylglycerol on the lipid bilayer of the membrane from acholeplasma laidlawii strain a-ef22. | the ability for 1,2-diacyl-3-o-(alpha-d-glucopyranosyl)-sn-glycerol (mglcdag) and 1,2-diacyl-3-o-(6-o-acyl-(alpha-d-glucopyranosyl))-sn-glycerol (mamglcdag) to induce non-lamellar phases in a lipid mixture with an in vivo composition, prepared from acholeplasma laidlawii membranes, has been investigated. the phase transition temperatures from lamellar to non-lamellar structures were studied with varying fractions of mglcdag and mamglcdag. the transition temperature decreased from 73 +/- 2 degree ... | 1995 | 7488623 |
| expression of foreign genes and selection of promoter sequences in acholeplasma laidlawii. | the stable maintenance and expression of foreign genes in mollicutes (mycoplasmas) have been difficult to achieve due to the lack of suitable vectors. in this paper we show for the first time that a replicating vector can been used to express foreign genes other than antibiotic resistance genes in acholeplasma laidlawii. plasmids derived from the lactococcal vector pnz18 could introduce and maintain four different genes for many generations in a. laidlawii. one of these, encoding the dominant me ... | 1995 | 7496518 |
| effects of pentachlorophenol and biotic interactions on soil fauna and decomposition in humus soil. | in a laboratory experiment, effects of chemical stress (pentachlorophenol, pcp, at concentrations of 0, 50, and 500 mg/kg) and biotic interactions (nematodes in the presence or absence of collembolas and enchytraeids) on the community structure of soil animals and decomposition processes were studied. pcp was strongly adsorbed to humus that contained 65% organic matter. numbers of fungal-feeding nematodes decreased significantly at the highest pcp concentration, while no effects were found in ba ... | 1995 | 7498064 |
| detection of alcohol-tolerant hiochi bacteria by pcr. | we report a sensitive and rapid method for detection of hiochi bacteria by pcr. this method involves the electrophoresis of amplified dna. nucleotide sequences of the spacer region between 16s and 23s rrna genes of 11 lactobacillus strains were identified by analysis of pcr products. five primers were designed by analysis of similarities among these sequences. a single cell of lactobacillus casei subsp. casei could be detected when purified genomic dna was used as the template. when various cell ... | 1994 | 7510942 |
| [oligodeoxyribonucleotides complementary to sections of the mollicute ribosomal operon as transcription inhibitors in vitro]. | antisense oligodeoxyribonucleotides have been studied for their effect on the transcription in vitro in mollicutes. a synthetic fragment of dna [symbol: see text] complementary to that part of dna which codes the 1510-1521 area of the 3'-terminal sequence 16s-prna of all mollicutes was used in the study as well as its modifications by imidasophenasine derivatives: [symbol: see text], [symbol: see text] [symbol: see text]. maximal inhibition of the mollicute transcription in vitro was observed wi ... | 1993 | 7517768 |
| phylogenetic classification of phytopathogenic mollicutes by sequence analysis of 16s ribosomal dna. | the phylogenetic relationships of 17 phytopathogenic mycoplasmalike organisms (mlos) representing seven major taxonomic groups established on the basis of mlo 16s ribosomal dna (rdna) restriction patterns were examined by performing a sequence analysis of the 16s rdna gene. the sequence data showed that the mlos which we examined are members of a relatively homogeneous group that evolved monophyletically from a common ancestor. in agreement with results obtained previously with other mlos, our r ... | 1994 | 7520735 |