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Journal of Bacteriology Aug 1965Somerson, Norman L. (National Institute of Allergy and Infectious Diseases, Bethesda, Md.), and M. K. Cook. Suppression of Rous sarcoma virus growth in tissue cultures...
Somerson, Norman L. (National Institute of Allergy and Infectious Diseases, Bethesda, Md.), and M. K. Cook. Suppression of Rous sarcoma virus growth in tissue cultures by Mycoplasma orale. J. Bacteriol. 90:534-540. 1965.-An agent which produced cell destruction in human diploid and chick-embryo fibroblasts was isolated from WI-26 strain of human diploid fibroblasts and shown to be a mycoplasma. The multiplication of Rous sarcoma virus (RSV) and Rous associated virus (RAV) was inhibited in WI-26, WI-38, and chick-embryo fibroblasts infected with this mycoplasma. The mycoplasma isolate, designated strain 941, reacted strongly in the complement-fixation test with antiserum to Mycoplasma orale CH19299, an isolate obtained from the human oral cavity. The cytopathic effect of mycoplasma strain 941 could be eliminated by growing the mycoplasma on an artificial agar medium before inoculation into chick-embryo fibroblasts. Serial passage in chick-embryo fibroblasts restored the cytopathogenicity of the agar-grown mycoplasma. However, growth of RSV and RAV was inhibited by both the tissue culture-grown and the agar-grown 941 strain, and also by the CH19299 strain which did not produce any cytopathic effect.
Topics: Agar; Animals; Antigen-Antibody Reactions; Avian Sarcoma Viruses; Chick Embryo; Complement Fixation Tests; Culture Media; Fibroblasts; Mycoplasma; Mycoplasma orale; Research; Rous sarcoma virus; Tissue Culture Techniques; Virus Cultivation
PubMed: 14329470
DOI: 10.1128/jb.90.2.534-540.1965 -
Journal of Thoracic Disease Feb 2022The current COVID-19 pandemic is posing a major challenge to public health on a global scale. While it is generally believed that severe COVID-19 results from...
BACKGROUND
The current COVID-19 pandemic is posing a major challenge to public health on a global scale. While it is generally believed that severe COVID-19 results from over-expression of inflammatory mediators (i.e., a "cytokine storm"), it is still unclear whether and how co-infecting pathogens contribute to disease pathogenesis. To address this, we followed the entire course of the disease in cases with severe or critical COVID-19 to determine the presence and abundance of all potential pathogens present-the total "infectome"-and how they interact with the host immune system in the context of severe COVID-19.
METHODS
We examined one severe and three critical cases of COVID-19, as well as a set of healthy controls, with longitudinal samples (throat swab, whole blood, and serum) collected from each case. Total RNA sequencing (meta-transcriptomics) was performed to simultaneously investigate pathogen diversity and abundance, as well as host immune responses, in each sample. A Bio-Plex method was used to measure serum cytokine and chemokine levels.
RESULTS
Eight pathogens, SARS-CoV-2, (), (), (), (), , herpes simplex virus (HSV) and human cytomegalovirus (CMV), identified in patients with COVID-19 appeared at different stages of the disease. The dynamics of inflammatory mediators in serum and the respiratory tract were more strongly associated with the dynamics of the infectome compared with SARS-CoV-2 alone. Correlation analysis revealed that pulmonary injury was directly associated with cytokine levels, which in turn were associated with the proliferation of SARS-CoV-2 and co-infecting pathogens.
CONCLUSIONS
For each patient, the cytokine storm that resulted in acute lung injury and death involved a dynamic and highly complex infectome, of which SARS-CoV-2 was a component. These results indicate the need for a precision medicine approach to investigate both the infection and host response as a standard means of infectious disease characterization.
PubMed: 35280492
DOI: 10.21037/jtd-21-1284 -
Cell Discovery Apr 2021Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic of Coronavirus disease 2019 (COVID-19). However, the microbial composition of...
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic of Coronavirus disease 2019 (COVID-19). However, the microbial composition of the respiratory tract and other infected tissues as well as their possible pathogenic contributions to varying degrees of disease severity in COVID-19 patients remain unclear. Between 27 January and 26 February 2020, serial clinical specimens (sputum, nasal and throat swab, anal swab and feces) were collected from a cohort of hospitalized COVID-19 patients, including 8 mildly and 15 severely ill patients in Guangdong province, China. Total RNA was extracted and ultra-deep metatranscriptomic sequencing was performed in combination with laboratory diagnostic assays. We identified distinct signatures of microbial dysbiosis among severely ill COVID-19 patients on broad spectrum antimicrobial therapy. Co-detection of other human respiratory viruses (including human alphaherpesvirus 1, rhinovirus B, and human orthopneumovirus) was demonstrated in 30.8% (4/13) of the severely ill patients, but not in any of the mildly affected patients. Notably, the predominant respiratory microbial taxa of severely ill patients were Burkholderia cepacia complex (BCC), Staphylococcus epidermidis, or Mycoplasma spp. (including M. hominis and M. orale). The presence of the former two bacterial taxa was also confirmed by clinical cultures of respiratory specimens (expectorated sputum or nasal secretions) in 23.1% (3/13) of the severe cases. Finally, a time-dependent, secondary infection of B. cenocepacia with expressions of multiple virulence genes was demonstrated in one severely ill patient, which might accelerate his disease deterioration and death occurring one month after ICU admission. Our findings point to SARS-CoV-2-related microbial dysbiosis and various antibiotic-resistant respiratory microbes/pathogens in hospitalized COVID-19 patients in relation to disease severity. Detection and tracking strategies are needed to prevent the spread of antimicrobial resistance, improve the treatment regimen and clinical outcomes of hospitalized, severely ill COVID-19 patients.
PubMed: 33850111
DOI: 10.1038/s41421-021-00257-2 -
BMC Research Notes Jan 2012During the routine laboratory cultivation of Lawsonia intracellularis, Mycoplasma contamination has been a frequent problem. When Mycoplasma contamination occurs in...
BACKGROUND
During the routine laboratory cultivation of Lawsonia intracellularis, Mycoplasma contamination has been a frequent problem. When Mycoplasma contamination occurs in laboratories that study L. intracellularis, the cultures must be discarded for 4 reasons: 1) Mycoplasma is inevitably concentrated along with L. intracellularis during the passage of L. intracellularis; 2) Mycoplasma inhibits the growth of L. intracellularis; and 3) it is impossible to selectively eliminate Mycoplasma in L. intracellularis cultures. In this study, we observed the contamination of Mycoplasma species during L. intracellularis cultivation among multiple laboratories.
RESULTS
The presence of a Mycoplasma infection in the L. intracellularis cultures was verified using polymerase chain reaction (PCR), and a sequence analysis of the partial 16S rRNA and 23S rRNA genes was performed. A PCR-based assay using genus-specific universal primers revealed that 29 (85.3%) of the 34 cultures were contaminated with Mycoplasma, including 26 with M. hyorhinis (89.2%), 2 with M. orale (6.9%), and 1 with M. fermentans (3.4%). The Mycoplasma contamination was not the result of infection with material of pig origin. McCoy cells, which are required for the cultivation of L. intracellularis, were also ruled out as the source of the Mycoplasma contamination.
CONCLUSIONS
In this study, M. hyorhinis was identified as the most common mollicute that contaminated L. intracellularis cultures. Whether L. intracellularis enhances the biological properties of Mycoplasma to promote infection in McCoy cells is not known. Because the McCoy cell line stocks that were used simultaneously were all negative for Mycoplasma, and the same worker handled both the McCoy cells to maintain the bacteria and the L. intracellularis cultures, it is possible that the L. intracellularis cultures are more vulnerable to Mycoplasma contamination. Taken together, these results suggest that continuous cultures of L. intracellularis must be tested for Mycoplasma contamination at regular intervals.The GenBank accession numbers for the sequences reported in this paper are JN689375 to JN689377.
PubMed: 22284165
DOI: 10.1186/1756-0500-5-78 -
Diagnostics (Basel, Switzerland) May 2021, , and sp. are atypical bacteria responsible for in vitro cell culture contaminations that can warp the results. These bacteria also cause human and animal infections...
, , and sp. are atypical bacteria responsible for in vitro cell culture contaminations that can warp the results. These bacteria also cause human and animal infections and may lead to chronic diseases. In developed polymerase chain reaction (PCR) in this study a quantitative PCR with SYBR Green I fluorochrome was applied to facilitate the , , and sp. DNA detection and identification. Screening Test-1 v.1 (triplex qPCR) allowed for the detection of 11 species. Test-1 v.2 (three single qPCRs) pre-identified three subgroups, allowing for the reduction of using single qPCRs in Test-2 for species identification. The range of both tests was consistent with pharmacopeial requirements for microbial quality control of mammal cells and included detection of , , , , , , , , , , and . Limit of detection values varied between 125-300 and 50-100 number of copies per milliliter in Test-1 and Test-2, respectively. Test-1 and Test-2 showed fully concordant results, allowed for time-saving detection and/or identification of selected species from , , and in tested cell cultures.
PubMed: 34068904
DOI: 10.3390/diagnostics11050876 -
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 Applied Microbiology Oct 2011To optimize growth conditions for preparation of stocks of mycoplasma reference strains to obtain highly viable and disperse samples with low ratios of genomic copy (GC)...
AIMS
To optimize growth conditions for preparation of stocks of mycoplasma reference strains to obtain highly viable and disperse samples with low ratios of genomic copy (GC) number to that of colony forming units (CFU). These stocks are required for assessment of relative limits of detection (LOD) of alternative nucleic acid testing (NAT)-based methods in comparison to the conventional microbiological methods.
METHODS AND RESULTS
A kinetics study was used to assess the changes in ratios between the numbers of GC and CFU at different growth phases of six different mycoplasma cultures Acholeplasma laidlawii, Mycoplasma gallisepticum, Mycoplasma arginini, Mycoplasma fermentans, Mycoplasma orale and Mycoplasma pneumoniae. All tested mycoplasmas demonstrated low GC/CFU ratios (≤ 10) within the log and early stationary growth phases. A significant increase in GC/CFU ratios was observed at the very late stationary and death phases, when the titre of cultures has declined. Similar patterns of GC/CFU profiles were observed for A. laidlawii and Myc. gallisepticum co-cultured with suspension of Chinese hamster ovary (CHO) cells.
CONCLUSIONS
Tested mycoplasma strains harvested at the exponential-early stationary phases of growth demonstrated the lowest GC/CFU ratios and low propensity to form filamentous structures or aggregates under proposed conditions and can be used for the preparation of a mycoplasma reference panel for methods comparability study.
SIGNIFICANCE AND IMPACT OF THE STUDY
This study shows that the preparation and use of viable mycoplasma reference strains with low CG/CFU ratios is the most reliable way to adequately evaluate the LOD of alternative NAT-based mycoplasma testing methods.
Topics: Animals; Bacteriological Techniques; CHO Cells; Coculture Techniques; Colony Count, Microbial; Cricetinae; Cricetulus; DNA, Bacterial; Evaluation Studies as Topic; Gene Dosage; Limit of Detection; Mycoplasma; Polymerase Chain Reaction; Reference Standards; Validation Studies as Topic
PubMed: 21794032
DOI: 10.1111/j.1365-2672.2011.05108.x -
Brazilian Journal of Microbiology :... 2014Mycoplasma spp, belongs to the class Mollicutes and is capable to produce alterations in cellular cultures causing damages to the biotechnological industry. Bioproducts...
Mycoplasma spp, belongs to the class Mollicutes and is capable to produce alterations in cellular cultures causing damages to the biotechnological industry. Bioproducts generally require two essential inputs, bovine serum and cells. The study herein aims to evaluate the mycoplasma concentrations that affect the growing of BHK21 and Vero cells. The species used were: Mycoplasma orale, M. salivarium, M. arginini and M. hyorhinis, cultivated in a SP4 media. Two contamination tests were performed with BHK21 and Vero cells and one of them applied different concentrations of mycoplasma. In the first one, mycoplasma was applied at the day zero and, in the second one, the contamination was performed after the monolayer establishment. The both cellular cultures presented cytopathic effects with mycoplasma contamination, but the Vero cells suffered more damages than the BHK21 ones. It was also observed that the severity of the cytopathic effect depended on the mycoplasma specie, on the concentration and on the time of contact with the cellular culture, which evidences the importance of controlling the presence of mycoplasma in biotechnological industries.
Topics: Animals; Cell Line; Chlorocebus aethiops; Coculture Techniques; Cricetinae; Culture Media; Epithelial Cells; Mycoplasma
PubMed: 25763061
DOI: 10.1590/s1517-83822014000400048 -
Journal of Clinical Pathology Dec 1971Mycoplasmas were sought in the salivary secretions and minor salivary gland tissue of 26 patients with Sjögren's syndrome or the allied sicca complex. A mycoplasma (M....
Mycoplasmas were sought in the salivary secretions and minor salivary gland tissue of 26 patients with Sjögren's syndrome or the allied sicca complex. A mycoplasma (M. orale type 1) was recovered from the stimulated parotid saliva of only one case. Possible mechanisms of mycoplasmal cell damage in this and allied disorders are considered and some future lines of investigation are suggested.
Topics: Adult; Aged; Culture Media; Female; Humans; Male; Middle Aged; Mycoplasma; Parotid Gland; Saliva; Salivary Glands; Sjogren's Syndrome
PubMed: 5139987
DOI: 10.1136/jcp.24.9.810 -
Applied and Environmental Microbiology Jan 1997Surfactin, a cyclic lipopeptide antibiotic and biosurfactant produced by Bacillus subtilis, is well-known for its interactions with artificial and biomembrane systems...
Surfactin, a cyclic lipopeptide antibiotic and biosurfactant produced by Bacillus subtilis, is well-known for its interactions with artificial and biomembrane systems (e.g., bacterial protoplasts or enveloped viruses). To assess the applicability of this antiviral and antibacterial drug, we determined the cytotoxicity of surfactin with a 50% cytotoxic concentration of 30 to 64 microM for a variety of human and animal cell lines in vitro. Concomitantly, we observed an improvement in proliferation rates and changes in the morphology of mycoplasma-contaminated mammalian cells after treatment with this drug. A single treatment over one passage led to complete removal of viable Mycoplasma hyorhinis cells from various adherent cell lines, and Mycoplasma orale was removed from nonadherent human T-lymphoid cell lines by double treatment. This effect was monitored by a DNA fluorescence test, an enzyme-linked immunosorbent assay, and two different PCR methods. Disintegration of the mycoplasma membranes as observed by electron microscopy indicated the mode of action of surfactin. Disintegration is obviously due to a physicochemical interaction of the membrane-active surfactant with the outer part of the lipid membrane bilayer, which causes permeability changes and at higher concentrations leads finally to disintegration of the mycoplasma membrane system by a detergent effect. The low cytotoxicity of surfactin for mammalian cells permits specific inactivation of mycoplasmas without significant deleterious effects on cell metabolism and the proliferation rate in cell culture. These results were used to develop a fast and simple method for complete and permanent inactivation of mycoplasmas in mammalian monolayer and suspension cell cultures.
Topics: Animals; Anti-Bacterial Agents; Bacillus subtilis; Bacterial Proteins; Cell Division; Cell Line; Drug Evaluation, Preclinical; Humans; Lipopeptides; Microscopy, Electron; Mycoplasma; Peptides, Cyclic
PubMed: 8979337
DOI: 10.1128/aem.63.1.44-49.1997