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Cytokine & Growth Factor Reviews 2004Mycoplasma pneumoniae (M. pneumoniae) is one of the smallest free-living bacteria known. Along with other unique characteristics of this genus, it lacks the typical... (Review)
Review
Mycoplasma pneumoniae (M. pneumoniae) is one of the smallest free-living bacteria known. Along with other unique characteristics of this genus, it lacks the typical peptidoglycan cell wall of most eubacteria. Best known for causing tracheobronchitis and atypical pneumonia in humans, this pathogen also causes a number of extrapulmonary syndromes such as meningitis/encephalitis and arthritis. Recent studies also suggest that infection may be associated with chronic conditions such as asthma. Although the mechanisms of M. pneumoniae pathogenesis remain to be elucidated, one important component of M. pneumoniae infections is the induction of proinflammatory and other cytokines in both acute and chronic conditions. In this review, we survey the induction of cytokines by M. pneumoniae in different model systems, and we discuss the possible role of induced cytokines in M. pneumoniae pathogenesis.
Topics: Animals; Cytokines; Humans; Mycoplasma Infections; Mycoplasma pneumoniae; Pneumonia, Mycoplasma
PubMed: 15110799
DOI: 10.1016/j.cytogfr.2004.01.001 -
Trends in Microbiology Jan 1998Mycoplasma pneumoniae has no cell wall but possesses a complex terminal structure that is required for polar localization of adhesins and is thought to participate in... (Review)
Review
Mycoplasma pneumoniae has no cell wall but possesses a complex terminal structure that is required for polar localization of adhesins and is thought to participate in cell division. Several protein components of this structure have been identified by analysis of non-cytadhering mutants. Genetic manipulation of mycoplasmas now allows elucidation of the assembly and regulation of the terminal organelle.
Topics: Amino Acid Sequence; Bacterial Adhesion; Bacterial Proteins; Gene Expression Regulation, Bacterial; Genome, Bacterial; Molecular Sequence Data; Mutation; Mycoplasma pneumoniae; Organelles
PubMed: 9481818
DOI: 10.1016/S0966-842X(97)01168-2 -
Current Drug Targets. Infectious... Sep 2005Mycoplasma pneumoniae is a pathogenic mycoplasma responsible for respiratory tract infections in humans, occurring worldwide in children and adults. This review briefly... (Review)
Review
Mycoplasma pneumoniae is a pathogenic mycoplasma responsible for respiratory tract infections in humans, occurring worldwide in children and adults. This review briefly focuses on its antibiotic susceptibility profile and on the development of acquired resistance for this microorganism. The lack of a cell wall in mycoplasmas makes them intrinsically resistant to beta-lactams and to all antimicrobials which target the cell wall. Intrinsic resistance related to specific mycoplasma species concerns essentially the acrolide-lincosamide-streptogramin-ketolide (MLSK) antibiotic group. M. pneumoniae is susceptible to all MLSK antibiotics, except to lincomycin. Among the three antibiotic classes used for the treatment of mycoplasmal infections including tetracyclines, MLSK group, and fluoroquinolones, macrolides and related antibiotics are the drug of choice for respiratory infections caused by M. pneumoniae. Both target alterations and efflux mechanisms implicated in acquired antibiotic resistance have been described in mycoplasmas either by genetic mutation or transfer of new genes carried by transposons. At present, M. pneumoniae remains greatly susceptible to antibiotics, but as this mycoplasma is difficult to isolate, the number of clinical strains tested is limited and the occurrence of acquired resistance not well documented. However some strains having acquired resistance to MLSK have been decribed in vivo and erythromycin-resistant isolates are spreading now in Japan. To date, no clinical isolates resistant to fluoroquinolones or tetracyclines have been described in the literature, but some strains having acquired resistance to both classes have been selected in vitro. Molecular diagnosis of this acquired resistance has been related to target alterations, in ribosome for macrolides and tetracyclines, or in topoisomerase II genes for fluoroquinolones.
Topics: Adult; Anti-Bacterial Agents; Child; Drug Resistance, Bacterial; Erythromycin; Fluoroquinolones; Humans; Mutation; Mycoplasma pneumoniae; Respiratory Tract Infections; Tetracyclines
PubMed: 16181145
DOI: 10.2174/1568005054880109 -
Current Opinion in Microbiology Oct 1998The rapid progress in sequencing large quantities of DNA will provide an increasing number of complete genome sequences of closely related bacterial species as well as... (Review)
Review
The rapid progress in sequencing large quantities of DNA will provide an increasing number of complete genome sequences of closely related bacterial species as well as of pairs of isolates from the same species with different features, such as a pathogenic and an apathogenic representative. This opens the way to apply subtractive comparative analysis as a tool to select from the large pool of all bacterial genes a relatively small set of genes that can be correlated with the expression of a certain phenotype. These selected genes can then be the target for further functional analyses.
Topics: Bacterial Proteins; Genes, Bacterial; Genome, Bacterial; Humans; Mycoplasma; Mycoplasma Infections; Mycoplasma pneumoniae; Sequence Analysis, DNA
PubMed: 10066529
DOI: 10.1016/s1369-5274(98)80091-x -
Frontiers in Bioscience : a Journal and... Jan 2007Mycoplasmas are unique cell wall deficient, cholesterol requiring, highly pleomorphic bacteria that possess very small genome. M. pneumoniae is an important human... (Review)
Review
Mycoplasmas are unique cell wall deficient, cholesterol requiring, highly pleomorphic bacteria that possess very small genome. M. pneumoniae is an important human pathogen that possesses specialized tip organelle to mediate cytadherence. It is a complex multifactorial process requiring a group of mycoplasma proteins such as P1, P30, P116 and HMW1-3. Expression of major mycoplasma adhesin proteins in heterologous expression systems provides an opportunity to study the role(s) of these proteins in pathogenicity and helps to develop diagnostic reagents. In this review we highlight the role(s) of various cytadhesin proteins of M. pneumoniae.
Topics: Adhesins, Bacterial; Genome, Bacterial; Humans; Mycoplasma pneumoniae; Pneumonia, Mycoplasma
PubMed: 17127329
DOI: 10.2741/2093 -
Military Medical Research Dec 2020In 2019, an outbreak of Mycoplasma pneumoniae occurred at a military academy in China. The attack rate (10.08%,60/595) was significantly different among the units....
In 2019, an outbreak of Mycoplasma pneumoniae occurred at a military academy in China. The attack rate (10.08%,60/595) was significantly different among the units. High-intensity training and crowded environments to which cadets are exposed are the high risk factors for the outbreak of M. pneumoniae. In-time prevention and control measures effectively controlled the spread of the epidemic.
Topics: Academies and Institutes; China; Disease Outbreaks; Humans; Military Personnel; Mycoplasma pneumoniae; Pneumonia, Mycoplasma
PubMed: 33272310
DOI: 10.1186/s40779-020-00289-x -
Israel Journal of Medical Sciences Jul 1981Mycoplasma pneumoniae represents one of the most common etiologic agents of lower respiratory tract disease of man. Data from a 12-yr period of surveillance in Seattle,...
Mycoplasma pneumoniae represents one of the most common etiologic agents of lower respiratory tract disease of man. Data from a 12-yr period of surveillance in Seattle, WA, USA, revealed that infection rates varied from 2% in endemic years to 35% in epidemic periods (J Infect Dis 139: 681, 1979). Most persons with M. pneumoniae infections have a relatively mild disease, which is not usually accompanied by frequent complications. Atypical pneumonia caused by the organisms is most prevalent in school-age children, with peak occurrence at about 10 years old. In this group, 13 to 18% of those infected develop pneumonia. Clinical disease is uncommon below 4 and above 50 years of age. M. pneumoniae infections probably occur throughout the world. It has been estimated that approximately 50% of the infections in adults but only 20% in children are completely asymptomatic. The usual clinical picture of atypical pneumonia and the wide range of unusual manifestations of M. pneumoniae disease are presented. Except for a few single case reports, histopathology of M. pneumoniae disease has been extensively studied after experimental infection of hamsters and guinea pigs. These animal models had to be developed because of the benign course of most M. Pneumoniae diseases in man. Due to this limited information on the pathology of natural disease, comments on its pathogenesis are also based on findings using experimental models. Infection is established by attachment of the organisms to the surface membrane of ciliated epithelial cells. Antigenic similarities between the glycolipids of M. pneumoniae membranes and host tissue, unspecific blastogenesis and immunosuppression during infection have been described. These phenomena may explain a decreased protective immune mechanism of the host during infection. Several as yet unexplained features of M. pneumoniae disease support the hypothesis that lung infiltrates in M. pneumoniae infection may be, in part, immunologically determined in a host sensitized by one or more silent infections.
Topics: Animals; Antibodies, Bacterial; Cell Membrane; Child, Preschool; Cricetinae; Guinea Pigs; Humans; Immunity; Infant; Macaca mulatta; Mycoplasma pneumoniae; Pneumonia, Mycoplasma
PubMed: 6793535
DOI: No ID Found -
Molecular Microbiology Apr 1996Mycoplasma pneumoniae is the leading cause of pneumonia in older children and young adults. Mycoplasma adherence to the respiratory epithelium (cytadherence) is required... (Review)
Review
Mycoplasma pneumoniae is the leading cause of pneumonia in older children and young adults. Mycoplasma adherence to the respiratory epithelium (cytadherence) is required for colonization and pathogenesis. Although considered to be among the smallest and simplest known prokaryotes, this cell-wall-less bacterium possesses a highly differentiated terminal structure that is thought to be functional in mycoplasma cell division, gliding motility, and cytadherence. Mutant analysis has identified mycoplasma proteins associated with cytadherence, and revealed novel regulatory features. Ultrastructural and biochemical studies have established the subcellular location and interaction of key components, several of which are phosphorylated by ATP-dependent kinase(s) in a manner that is responsive to changing nutritional conditions. This review summarizes recent progress in defining the composition, organization and regulation of the attachment organelle. What emerges is a picture of M. pneumoniae cytadherence as a multifactorial process that extends well beyond adhesin-receptor recognition.
Topics: Adhesins, Bacterial; Bacterial Adhesion; Gene Expression Regulation, Bacterial; Humans; Mycoplasma pneumoniae
PubMed: 8733224
DOI: 10.1111/j.1365-2958.1996.tb02613.x -
Expert Review of Anti-infective Therapy Aug 2008Mycoplasma pneumoniae is one of the most common agents of community-acquired pneumonia in children and young adults. Although M. pneumoniae is a small bacterium that can... (Review)
Review
Mycoplasma pneumoniae is one of the most common agents of community-acquired pneumonia in children and young adults. Although M. pneumoniae is a small bacterium that can reproduce in an artificial culture medium and is known to be sensitive to certain antibiotics in vitro as well as in vivo, the immunopathogenesis of M. pneumoniae in the human host is not fully understood. The epidemiologic characteristics, including periodic epidemics, and some clinical characteristics of M. pneumoniae are similar to those observed in systemic viral infections. Many experimental and clinical studies have suggested that the pathogenesis of lung injuries in M. pneumoniae infection is associated with a cell-mediated immune reaction, including high responsiveness to corticosteroid therapy. This paper presents an overview of M. pneumoniae infections, with emphasis on epidemiology, pathogenesis and treatment.
Topics: Child; Community-Acquired Infections; Disease Outbreaks; Humans; Mycoplasma pneumoniae; Pneumonia, Mycoplasma
PubMed: 18662117
DOI: 10.1586/14787210.6.4.509 -
Cellular Microbiology Jun 2019Epithelial cell shedding is a defence mechanism against infectious microbes that use these cells as an infection foothold and that eliminate microbes from infection foci...
Epithelial cell shedding is a defence mechanism against infectious microbes that use these cells as an infection foothold and that eliminate microbes from infection foci by removing infected cells. Mycoplasma pneumoniae, a causative agent of respiratory infections, is known to adhere to and colonise the surface of ciliated airway epithelial cells; it produces a large amount of hydrogen peroxide, indicating its capability of regulating hydrogen peroxide-induced infected cell detachment. In this study, we found that M. pneumoniae reduces exogenous hydrogen peroxide-induced detachment of the infected cells from culture plates. This cell detachment occurred dependently of DNA damage-initiated, poly (ADP-ribose) polymerase 1 (PARP1)-mediated cell death, or parthanatos. In cells infected with M. pneumoniae, exogenous hydrogen peroxide failed to induce DNA damage-initiated poly (ADP-ribose) (PAR) synthesis and concomitant increased cytoplasmic membrane rupture, both of which are biochemical hallmarks of parthanatos. The impairment of PAR synthesis was attributed to a reduction in the amount of cytosolic nicotinamide adenine dinucleotide (NAD), a substrate of PARP1, caused by M. pneumoniae. On the other hand, nonadherent mutant strains of M. pneumoniae showed a lower ability to reduce cell detachment than wild-type strains, but the extent to which NAD was decreased in infected cells was comparable to that seen in the wild-type strain. We found that NAD depletion could induce PARP1-independent cell detachment pathways following stimulation with hydrogen peroxide and that M. pneumoniae could also regulate PARP1-independent cell detachment in a cytoadhesion-dependent manner. These results suggest that M. pneumoniae might regulate infected cell detachment induced by hydrogen peroxide that it produces itself, and such a mechanism may contribute to sustaining the bacterial infection.
Topics: Apoptosis; Cell Adhesion; DNA Damage; Epithelial Cells; Humans; Hydrogen Peroxide; Mycoplasma pneumoniae; NAD; Parthanatos; Poly (ADP-Ribose) Polymerase-1; Reactive Oxygen Species
PubMed: 30702185
DOI: 10.1111/cmi.13015