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Microbiologia Espanola 1984
Topics: Humans; In Vitro Techniques; Mouth; Mycoplasma; Pharynx
PubMed: 6535925
DOI: No ID Found -
Applied Microbiology Jul 1972Five nonionic detergents (Tweens 20, 40, 60, and 80, and Triton WR-1339) were tested for their ability to inactivate four Mycoplasma species which are common...
Five nonionic detergents (Tweens 20, 40, 60, and 80, and Triton WR-1339) were tested for their ability to inactivate four Mycoplasma species which are common contaminants of animal cell cultures. Tween 20 was found to be the most effective, in that a concentration of 2.5 mg/ml completely inactivated cultures of M. hominis, M. hyorhinis, and Acholeplasma laidlawii within 1 hr and a culture of M. orale within 3 hr. The other detergents exhibited various degree of activity against the different mycoplasmas, with Triton WR-1339 being the least effective. The virucidal activity of the detergents was determined for six viruses. All four Tween compounds were highly virucidal for herpes simplex virus. Tween 20 also exhibited virucidal effects against vesicular stomatitis virus, California encephalitis virus, and Newcastle disease virus, and Tween 80 was found to be active against California encephalitis and Newcastle disease viruses. Detergent treatment procedures were effective in two instances in eliminating mycoplasma contaminants from virus preparations while the preparations retained most of the viral infectivity. The limitations of this technique for routine use are discussed.
Topics: Animals; Anti-Bacterial Agents; Anti-Infective Agents; Antiviral Agents; Bacteriological Techniques; Cell Line; Chick Embryo; Cricetinae; Culture Techniques; Drug Resistance, Microbial; Encephalitis Viruses; Humans; Kidney; Lung; Mycoplasma; Newcastle disease virus; Poliovirus; Simplexvirus; Species Specificity; Surface-Active Agents; Time Factors; Vaccinia virus; Vesicular stomatitis Indiana virus; Virus Cultivation
PubMed: 4341521
DOI: 10.1128/am.24.1.18-21.1972 -
International Journal of Cancer Mar 2022Colonization of specific bacteria in the human mouth was reported to be associated with gastric cancer risk. However, previous studies were limited by retrospective...
Colonization of specific bacteria in the human mouth was reported to be associated with gastric cancer risk. However, previous studies were limited by retrospective study designs and low taxonomic resolutions. We performed a prospective case-control study nested within three cohorts to investigate the relationship between oral microbiome and gastric cancer risk. Shotgun metagenomic sequencing was employed to characterize the microbiome in prediagnostic buccal samples from 165 cases and 323 matched controls. Associations of overall microbial richness and abundance of microbial taxa, gene families and metabolic pathways with gastric cancer risk were evaluated via conditional logistic regression. Analyses were performed within each cohort, and results were combined by meta-analyses. We found that overall microbial richness was associated with decreased gastric cancer risk, with an odds ratio (OR) per standard deviation (SD) increase in Simpson's reciprocal index of 0.77 (95% confidence interval [CI] = 0.61-0.99). Nine taxa, 38 gene families and six pathways also showed associations with gastric cancer risk at P < .05. Neisseria mucosa and Prevotella pleuritidis were enriched, while Mycoplasma orale and Eubacterium yurii were depleted among cases with ORs and 95% CIs per SD increase in centered log-ratio transformed taxa abundance of 1.31 (1.03-1.67), 1.26 (1.00-1.57), 0.74 (0.59-0.94) and 0.80 (0.65-0.98), respectively. The top two gene families (P = 3.75 × 10 and 3.91 × 10 ) and pathways (P = 1.75 × 10 and 1.53 × 10 ) associated with gastric cancer were related to the decreased risk and are involved in hexitol metabolism. Our study supports the hypothesis that oral microbiota may play a role in gastric cancer etiology.
Topics: Adult; Black or African American; Aged; Asian People; Female; Gastrointestinal Microbiome; Humans; Male; Metabolic Networks and Pathways; Middle Aged; Mouth; Prospective Studies; Risk; Stomach Neoplasms; White People
PubMed: 34664266
DOI: 10.1002/ijc.33847 -
Journal of Microbiological Methods Jan 2000A detection system that utilizes a primer mixture in a nested polymerase chain reaction for detecting Mycoplasma contaminants in cell cultures is described. Primers were...
A detection system that utilizes a primer mixture in a nested polymerase chain reaction for detecting Mycoplasma contaminants in cell cultures is described. Primers were designed to amplify the spacer regions between the 16S and 23S ribosomal RNA genes of Mycoplasma and Acholeplasma. This detection system was able to detect 20-180 colony forming units per milliliter of sample. Eight commonly encountered Mycoplasma and Acholeplasma contaminants, which include Mycoplasma (M.) arginini, M. fermentans, M. hominis, M. hyorhinis, M. orale, M. pirum, M. salivarium, and Acholeplasma laidlawii, were consistently amplified. Mycoplasma contaminants generated a single DNA band of 236-365 base pairs (bp), whereas A. laidlawii produced a characteristic two-band pattern of 426 and 219 bp amplicons. Species identification could be achieved by size determination and restriction enzyme digestion. Minor cross-reactions were noted with a few closely related gram positive bacteria and DNA from rat cell lines. A Mycoplasma Detection Kit for detecting Mycoplasma contaminants in cell cultures has been developed based on this approach.
Topics: Acholeplasma laidlawii; Animals; Cell Culture Techniques; Genes, rRNA; Humans; Mice; Mycoplasma; Polymerase Chain Reaction; RNA, Ribosomal, 16S; RNA, Ribosomal, 23S; Rats; Sensitivity and Specificity
PubMed: 10576701
DOI: 10.1016/s0167-7012(99)00107-4 -
Leukemia Research Aug 1992Thirty-nine continuous adherent or suspension cell lines were treated with a quinolone antibiotic, Mycoplasma Removal Agent (MRA), for the elimination of chronic...
Thirty-nine continuous adherent or suspension cell lines were treated with a quinolone antibiotic, Mycoplasma Removal Agent (MRA), for the elimination of chronic mycoplasma contamination. In preliminary experiments MRA did not show any cytostatic or cytotoxic effects on mycoplasma-free cell cultures in concentrations up to ten-fold the concentration used for mycoplasma eradication. Twenty-eight cell lines (72%) were effectively cleansed of the mycoplasma contaminants by MRA treatment. The persistent removal of the mycoplasma infection was monitored by three mycoplasma detection assays. In seven cell lines (18%) the mycoplasmas were resistant to treatment with MRA. The resistant species was mainly M. arginini followed by M. orale and A. laidlawii; however, other cell lines harboring these species were cured. Four cell lines (10%) which prior to treatment presented with decreased viability and poor or no cell growth were lost during or shortly after the exposure to the antibiotic. If an antibiotic elimination is attempted it is imperative to closely examine the effectiveness of treatment and possible eukaryotic cytotoxicity. The treated mycoplasma-free cells may also no longer express the original features as a result of treatment or the absence of mycoplasma.
Topics: Cell Survival; Drug Resistance, Microbial; Humans; Mycoplasma; Quinolones; Tumor Cells, Cultured
PubMed: 1326687
DOI: 10.1016/0145-2126(92)90161-y -
Biologicals : Journal of the... Mar 2008A panel of 30 putative Mycoplasma fermentans strains, isolated from various sources including human, ovine and cell lines, were tested by a previously described...
A panel of 30 putative Mycoplasma fermentans strains, isolated from various sources including human, ovine and cell lines, were tested by a previously described polymerase chain reaction (PCR) to confirm their identity by amplification of a conserved 206 bp region of the insertion sequence IS1550. In addition, the application of another PCR based on the major part of the IS1550 element showed one or two products of different length (1144 and 1341 bp) enabling M. fermentans strains to be divided into two types designated as Type A and Type B. A PCR, which amplifies the macrophage activating lipopeptide gene (malp), supported the identification of all the strains as M. fermentans. Thirteen other species of Mycoplasma from human sources gave negative results in these tests, with the exception of Mycoplasma orale, which was detected by both IS1550-PCRs based on the major part and the conserved 206 bp region of the IS1550 element. This study suggests that all M. fermentans isolates possess both the IS1550 element and the malp gene. In contrast to the IS1550, the malp gene is shown to be species-specific and the use of a malp PCR described here could prove to be a useful adjunct to IS1550 detection as confirmation of the presence of M. fermentans in clinical material.
Topics: Animals; Cell Line; DNA, Bacterial; DNA, Ribosomal; Humans; Mycoplasma fermentans; Polymerase Chain Reaction; RNA, Ribosomal, 16S; Sequence Analysis, DNA; Sheep
PubMed: 17892949
DOI: 10.1016/j.biologicals.2007.07.003 -
Infection and Immunity Jun 1980The ability of a mouse mammary tumor cell line to abrogate antibody neutralization of vesicular stomatitis virus was shown to be due to the presence of mycoplasma. The...
The ability of a mouse mammary tumor cell line to abrogate antibody neutralization of vesicular stomatitis virus was shown to be due to the presence of mycoplasma. The mycoplasma was isolated from the cell line and typed as Mycoplasma orale. Colonies of this mycoplasma were used to deliberately infect cell cultures which then gained the capacity to reactivate antibody-neutralized virus. The extent of the reactivation depended on the source of neutralizing antiserum. Other species of mycoplasma were tested and were found to reactivate neutralized virus, indicating that this may be a general phenomenon of mycoplasma contamination.
Topics: Animals; Antibodies, Viral; Antigen-Antibody Reactions; Cell Line; Mink; Mycoplasma; Neutralization Tests; Vesicular stomatitis Indiana virus; Virus Activation
PubMed: 6249748
DOI: 10.1128/iai.28.3.649-653.1980 -
Applied Microbiology Feb 1971Eight Mycoplasma species of human origin were successfully cultivated on glass. Complement-fixing (CF) antigens prepared from glass-adherent mycoplasmas were potent,...
Eight Mycoplasma species of human origin were successfully cultivated on glass. Complement-fixing (CF) antigens prepared from glass-adherent mycoplasmas were potent, specific, and free from anticomplementary activity. PPLO broth medium supplemented with 1 to 5% PPLO serum fraction (bovine), 2.5% fresh yeast extract, and 1% glucose (glycolytic species) or 1% arginine (arginine-utilizing species) supported moderate to luxuriant growth of mycoplasmas on glass. The potency of CF antigens prepared from glass-adherent mycoplasmas varied with the species of Mycoplasma tested and the duration of incubation. When the potency of CF antigens prepared from glass-adherent mycoplasmas was compared with that material sedimented from the broth phase of the same culture, three patterns of growth were observed: M. hominis and M. orale type 2 grew preferentially in the broth phase; M. salivarium, M. orale types 1 and 3, M. pneumoniae, and M. lipophilum preferentially adhered to the glass; and M. fermentans was biphasic. The growth of mycoplasmas on glass provides a simple means of concentrating and purifying such organisms for immunological and biochemical studies.
Topics: Acetates; Age Factors; Animals; Antigens; Arginine; Bacteriological Techniques; Cattle; Complement Fixation Tests; Culture Media; Glass; Glucose; Horses; Hot Temperature; Humans; Hydrogen-Ion Concentration; Immune Sera; Indicators and Reagents; Mycoplasma; Penicillins; Rabbits; Saccharomyces; Species Specificity; Thallium; Time Factors; Yeast, Dried
PubMed: 5547544
DOI: 10.1128/am.21.2.288-294.1971 -
In Vitro May 1984Infection of cell cultures by mycoplasmas can be detected and the mycoplasma identified by Southern blot hybridization of the Eco RI-digested DNA of the suspected cell...
Infection of cell cultures by mycoplasmas can be detected and the mycoplasma identified by Southern blot hybridization of the Eco RI-digested DNA of the suspected cell cultures with a nick-translated probe consisting of cloned ribosomal RNA genes of Mycoplasma capricolum. The probe does not hybridize with eukaryotic DNA. The hybridization pattern with mycoplasmal DNA is species specific, enabling the identification of the four most prevalent mycoplasma contaminants, Mycoplasma orale, Mycoplasma hyorhinis, Mycoplasma arginini, and Acholeplasma laidlawii. The test is also very sensitive and can detect as little as 1 ng of mycoplasmal DNA, roughly equivalent to the DNA content of 10(5) mycoplasmas.
Topics: Animals; Cloning, Molecular; Culture Media; Culture Techniques; DNA, Fungal; L Cells; Mice; Mycoplasma; Nucleic Acid Hybridization
PubMed: 6724620
DOI: 10.1007/BF02619586 -
The Biochemical Journal Jun 1983A collagenase previously reported to accumulate in the medium of cultures of BALB/c 3T3 cells on infection with Mycoplasma orale [Kluve, Merrick, Stanbridge & Gershman...
A collagenase previously reported to accumulate in the medium of cultures of BALB/c 3T3 cells on infection with Mycoplasma orale [Kluve, Merrick, Stanbridge & Gershman (1981) Nature (London) 292, 855-857] was partially purified and characterized. With regard to purification properties, activation, sensitivity to inhibitors and relative molecular mass the enzyme was similar to previously reported vertebrate collagenases, but could not be unequivocally distinguished from bacterial collagenases. With regard to substrate-specificity and reaction products, however, the collagenase was typical of vertebrate collagenases and distinct from bacterial collagenases. Specifically, the enzyme displayed a preference for type III collagen and type I collagen, a somewhat decreased ability to degrade type II collagen, and a very limited ability to degrade type IV collagen. The initial products of the action of the collagenase on type I collagen were characterized as fragments one-quarter and three-quarters of the length of the intact collagen molecule. Because the properties of the collagenase produced by cultures of mycoplasma-infected BALB/c 3T3 cells are those of a mammalian-type (vertebrate-type) enzyme, we have concluded that the collagenase is a product of the mouse (BALB/c 3T3) genome, and is not produced by the mycoplasma. Therefore it appears that infection of BALB/c 3T3 mouse fibroblasts with Mycoplasma orale induces the mouse cells to produce and secrete collagenase.
Topics: Animals; Cell Line; Chromatography, Ion Exchange; Collagen; Electrophoresis, Polyacrylamide Gel; Enzyme Induction; Fibroblasts; Kinetics; Mice; Mice, Inbred BALB C; Microbial Collagenase; Mycoplasma; Substrate Specificity
PubMed: 6309150
DOI: 10.1042/bj2120641