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1.
J Infect Dis ; 220(12): 1999-2008, 2019 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-31420650

RESUMO

Mycoplasma lipoproteins play a relevant role in pathogenicity and directly interact with the host immune system. Among human mycoplasmas, Mycoplasma hominis is described as a commensal bacterium that can be associated with a number of genital and extragenital conditions. Mechanisms of M. hominis pathogenicity are still largely obscure, and only a limited number of proteins have been associated with virulence. The current study focused on investigating the role of MHO_0730 as a virulence factor and demonstrated that MHO_0730 is a surface lipoprotein, potentially expressed in vivo during natural infection, acting both as a nuclease with its amino acidic portion and as a potent inducer of Neutrophil extracellular trapsosis with its N-terminal lipid moiety. Evidence for M. hominis neutrophil extracellular trap escape is also presented. Results highlight the relevance of MHO_0730 in promoting infection and modulation and evasion of innate immunity and provide additional knowledge on M. hominis virulence and survival in the host.


Assuntos
Proteínas de Bactérias/metabolismo , Armadilhas Extracelulares/imunologia , Armadilhas Extracelulares/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Infecções por Mycoplasma/imunologia , Infecções por Mycoplasma/microbiologia , Mycoplasma hominis/fisiologia , Humanos , Lipoproteínas/metabolismo , Infecções por Mycoplasma/metabolismo , Mycoplasma hominis/enzimologia , Neutrófilos/imunologia , Neutrófilos/metabolismo , Transporte Proteico , Proteínas Recombinantes , Virulência
2.
Anal Chim Acta ; 800: 87-94, 2013 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-24120172

RESUMO

In this contribution we present a sensitive colorimetric bioactive paper fabricated to determine sialidase-related diseases like bacterial vaginosis (BV) in a one-step and dry format spot assay with fast response and good storage stability. The paper was prepared by three simple steps. The first step involves preparation of poly(ethyleneimine) (PEI) microcapsules, the second step is to incubate positively charged microcapsules in negatively charged 5-bromo-4-chloro-3-indolyl-a-D-N-acetylneuraminic acid (BCIN) solution, a color enhancer nitro blue tetrazolium (NBT), and in the third step, paper was fabricated by incorporating incubated microcapsules into paper pulp. This paper changes color from white to dark purple in the presence of sialidase in as little as 6min, and color could be enhanced with increased length of reaction time. In this reaction system, BCIN was the substrate for sialidase, NBT was the color enhancer, and PEI microcapsules acted as catalyst. The loading efficiency of BCIN was about 22.2%, and filtered BCIN solution could be reused for the next fabrication.


Assuntos
Colorimetria , Papel , Kit de Reagentes para Diagnóstico/normas , Vaginose Bacteriana/diagnóstico , Cápsulas/química , Feminino , Gardnerella vaginalis/enzimologia , Gardnerella vaginalis/isolamento & purificação , Humanos , Mobiluncus/enzimologia , Mobiluncus/isolamento & purificação , Mycoplasma hominis/enzimologia , Mycoplasma hominis/isolamento & purificação , Ácido N-Acetilneuramínico/análogos & derivados , Ácido N-Acetilneuramínico/química , Ácido N-Acetilneuramínico/metabolismo , Neuraminidase/metabolismo , Polietilenoimina/química , Sais de Tetrazólio/química , Vaginose Bacteriana/microbiologia
3.
J Biotechnol ; 167(4): 420-6, 2013 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-23928331

RESUMO

Arginine deiminase is a promising anticancer drug active against melanoma, hepatocarcinoma and other tumors. Recombinant strains of Escherichia coli that express arginine deiminase from pathogenic bacteria Mycoplasma have been developed. However, production costs of heterologous arginine deiminase are high due to use of an expensive inducer and extraction buffer, as well as using diluted culture for enzyme induction. We report on a new advanced protocol for Mycoplasma hominis arginine deiminase expression, extraction and renaturation. The main improvements include manipulation with dense suspensions of E. coli, use of lactose instead of isopropyl ß-D-1-thiogalactopyranoside as an inducer and a cheaper but not less efficient buffer for solubilization of arginine deiminase inclusion bodies. In addition, supplementation of the storage culture medium with glucose and substrate (arginine) significantly stabilized the recombinant arginine deiminase producer. Homogenous preparations of recombinant arginine deiminase were obtained using anion-exchange and hydrophobic chromatography. The purified enzyme retained a specific activity of 30-34 U/mg for 12 months when stored at 4°C in 20 mM sodium phosphate buffer pH 7.2 containing 1 M NaCl.


Assuntos
Clonagem Molecular , Escherichia coli/enzimologia , Hidrolases/isolamento & purificação , Hidrolases/metabolismo , Mycoplasma hominis/enzimologia , Antineoplásicos/farmacologia , Biotecnologia , Meios de Cultura , Escherichia coli/genética , Hidrolases/economia , Hidrolases/genética , Corpos de Inclusão , Lactose/metabolismo , Mutagênese Sítio-Dirigida , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo
4.
BMC Microbiol ; 11: 185, 2011 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-21854595

RESUMO

BACKGROUND: In Mycoplasma hominis, a facultative human pathogen of the human genital tract, OppA, the substrate-binding domain of the oligopeptide permease, is a multifunctional protein involved in nutrition uptake, cytoadhesion and hydrolysis of extracellular ATP. RESULTS: To map the function-related protein regions the ATPase activity and adhesive behavior of OppA mutants were analyzed. Mutations of the Walker BA motifs resulted in an inhibition of up to 8% of the OppA ATPase activity, whereas deletion of the N-terminal CS1 or the CS2 region, structural motifs that are conserved in bacterial OppA proteins, reduced ATPase activity to 60% and deletion of CS3, the third conserved region adjacent to the Walker B motif led to a reduction to 42% ATPase activity. Interestingly, adhesion of the OppA mutants to immobilized HeLa cells demonstrated that two distal regions are mainly involved in adherence of OppA: the CS1 region, deletion of which led to 35% of the cytoadhesion, and the Walker BA with the adjacent upstream region CS3, deletion of which led to 25% of the cytoadhesion. The influence of the ATPase activity on the adherence of M. hominis to HeLa cells was confirmed by the use of ATPase inhibitors which reduced mycoplasmal cytoadhesion to 50%. CONCLUSIONS: These findings suggest that the OppA-mediated cytoadherence of Mycoplasma hominis depends on both, the topology of the neighbouring CS1 and ATPase domain regions and the functionality of the ecto-ATPase activity in addition.


Assuntos
Adenosina Trifosfatases/metabolismo , Aderência Bacteriana , Proteínas de Bactérias/metabolismo , Proteínas de Transporte/metabolismo , Lipoproteínas/metabolismo , Infecções por Mycoplasma/microbiologia , Mycoplasma hominis/fisiologia , Adenosina Trifosfatases/química , Adenosina Trifosfatases/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Transporte/química , Proteínas de Transporte/genética , Células HeLa , Humanos , Lipoproteínas/química , Lipoproteínas/genética , Mycoplasma hominis/química , Mycoplasma hominis/enzimologia , Mycoplasma hominis/genética , Estrutura Terciária de Proteína
5.
J Vet Med Sci ; 71(10): 1343-7, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19887741

RESUMO

We have cloned the arginine deiminase (ADI) gene from Mycoplasma hominis PG21 genomic DNA by polymerase chain reaction, and changed four TGA tryptophan codons (stop codon in E. coli) to TGG codons in the coding region by site-directed mutagenesis in order to express in E. coli. The recombinant ADI (rADI) was purified to apparent homogeneity by Ni-affinity chromatography after extraction from inclusion bodies followed by refolding. The rADI expressed in E. coli was estimated to be 50 kDa. Dimeric forms of rADI exerted enzymatic activity. We found that high concentration of potassium dihydrogenphosphate (PDP) and L-arginine addition in refolding reaction increases the enzyme activity. The specific activity of rADl was calculated as 0.618 U/mg. In addition, the enzyme activity of purified rADI remained for at least one month in 100 mM PDP solution (pH 6.5), but diminished within one week in 100 mM PDP solution (pH 7.4). Anti-tumor activity of the purified rADI was estimated to be 0.036 U/ml as 50% growth inhibitory activity against human melanoma cell line G-361.


Assuntos
Hidrolases/metabolismo , Hidrolases/farmacologia , Melanoma/metabolismo , Mycoplasma hominis/enzimologia , Proteínas Recombinantes , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Regulação Bacteriana da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Humanos , Hidrolases/química , Hidrolases/genética
6.
BMC Microbiol ; 8: 55, 2008 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-18394151

RESUMO

BACKGROUND: In the facultative human pathogen Mycoplasma hominis, which belongs to the cell wall-less Mollicutes, the surface-localised substrate-binding domain OppA of the oligopeptide permease was characterised as the main ecto-ATPase. RESULTS: With the idea that extra-cellular ATP could only be provided by the infected host cells we analysed the ATP release of HeLa cells after incubation with different preparations of Mycoplasma hominis: intact bacterial cells, the membrane fraction with or without OppA, recombinant OppA as well as an ATPase-deficient OppA mutant. Release of ATP into the supernatant of the HeLa cells was primarily determined in all samples lacking ecto-ATPase activity of OppA. In the presence of the ATPase inhibitor DIDS the amount of ATP in the OppA-containing samples increased. This increase was maximal after incubation with fractions containing OppA protein indicating that OppA is involved in ATP release and subsequent hydrolysis. Real-time PCR analyses revealed that the proliferation of HeLa cells is reduced after infection with M. hominis and flow cytometry experiments established that OppA induces greater apoptosis than necrosis of HeLa cells whereas the preservation of ecto-ATPase activity of OppA induces apoptosis. CONCLUSION: The OppA induced ATP-release and -hydrolysis induced cell death of M. hominis infected HeLa cells was predominantly due to apoptosis rather than necrosis. Future work will elucidate whether the induction of apoptosis is indispensable for survival of these non-invasive pathogen.


Assuntos
Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Transporte/metabolismo , Lipoproteínas/metabolismo , Mycoplasma hominis/enzimologia , Oligopeptídeos/metabolismo , Morte Celular , Células HeLa/metabolismo , Células HeLa/patologia , Humanos , Hidrólise
7.
Proteins ; 66(3): 740-50, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-17080455

RESUMO

Arginine deiminase (ADI) catalyzes the irreversible hydrolysis of arginine to citrulline and ammonia. It belongs to a newly classified superfamily of guanidino-group-modifying enzymes. Located in the catalytic center of Mycoplasma hominis ADI, some crucial sites (Asp160, Glu212, His268, and Asp270) are highly conserved among these enzymes. Here, we constructed five ADI single mutants D160E, E212D, H268F, H268Y, and D270E, and three double mutants D160E/D270E, D160E/E212D, and E212D/D270E, aiming to evaluate the contributions of these crucial residues to the structure, stability, and enzymatic activity of ADI, and to elucidate their roles in the catalytic process of this family of enzymes. Tryptophan emission fluorescence and circular dichroism were used to analyze the different effects of mutagenesis on these conserved residues on the secondary and tertiary structures of ADI. Urea-induced unfolding and trypsin digestion were applied to measure their stabilities against denaturants and proteases, respectively. Additionally, the enzymatic activities of ADI and its mutants were measured. Here, we report that all the mutations have little effect on the native structure of ADI. However, the substitutions on these crucial sites still interfere with the stability of ADI to different degrees. As these mutations impair both the substrate binding and the substrate induced conformational changes of ADI to different extents, most of the mutants except D160E (preserves about 30% of the enzymatic activity of wild type) have totally lost the enzymatic activity in the hydrolysis of arginine and the inhibitory ability on the proliferation of mouse melanoma cells.


Assuntos
Hidrolases/química , Hidrolases/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Catálise , Dicroísmo Circular , Cinética , Modelos Moleculares , Mycoplasma hominis/enzimologia , Conformação Proteica , Desnaturação Proteica , Dobramento de Proteína , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Espectrometria de Fluorescência
8.
Expert Opin Investig Drugs ; 15(7): 815-22, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16787144

RESUMO

Pegylated arginine deiminase (ADI-PEG20) is a novel anticancer enzyme that produces depletion of arginine, which is a nonessential amino acid in humans. Certain tumours, such as malignant melanoma and hepatocellular carcinoma, are auxotrophic for arginine. These tumours that are sensitive to arginine depletion do not express argininosuccinate synthetase, a key enzyme in the synthesis of arginine from citrulline. ADI-PEG20 inhibits human melanomas and hepatocellular carcinomas in vitro and in vivo. Phase I - II trials in patients with melanoma and hepatocellular carcinomas have shown the drug to have antitumour activity and tolerable side effects. Large Phase II trials and randomised, controlled Phase III trials are needed to determine its overall efficacy in the treatment of these malignancies and others.


Assuntos
Antineoplásicos/uso terapêutico , Arginina/metabolismo , Drogas em Investigação/uso terapêutico , Hidrolases/uso terapêutico , Neoplasias/tratamento farmacológico , Polietilenoglicóis/uso terapêutico , Sequência de Aminoácidos , Aminoácidos/metabolismo , Animais , Antineoplásicos/farmacologia , Argininossuccinato Sintase/deficiência , Argininossuccinato Sintase/metabolismo , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/enzimologia , Citrulina/metabolismo , Ensaios Clínicos como Assunto , Dexametasona/farmacologia , Cães , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Drogas em Investigação/farmacologia , Humanos , Hidrolases/imunologia , Hidrolases/farmacologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/enzimologia , Melanoma/tratamento farmacológico , Melanoma/enzimologia , Melanoma Experimental/tratamento farmacológico , Camundongos , Camundongos Nus , Dados de Sequência Molecular , Mycoplasma hominis/enzimologia , Mycoplasma hominis/genética , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Necessidades Nutricionais , Polietilenoglicóis/farmacologia , Coelhos , Ensaios Clínicos Controlados Aleatórios como Assunto , Proteínas Recombinantes/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/enzimologia , Especificidade da Espécie , Resultado do Tratamento
9.
J Bacteriol ; 186(4): 1021-928, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14761996

RESUMO

Most ATPases, involved in energy-driven processes, act in the cytoplasm. However, external membrane-bound ATPases have also been described in parasites and eukaryotic cells. In Mycoplasma hominis, a bacterium lacking a cell wall, the surface-exposed substrate-binding protein OppA of an oligopeptide permease (Opp) contains an ATP binding P-loop structure in the C-terminal region. With ATP affinity chromatography and tryptic digestion in the presence or absence of ATP, the functionality of the Mg(2+)-dependent ATP binding site is demonstrated. In addition to ATP, ADP also could bind to OppA. The presence of an ATPase activity on the surface of M. hominis is indicated by the inactivation of ATP hydrolyzing activity of intact mycoplasma cells by the impermeable ATPase inhibitor 4',4'-diisothiocyanostilbene-2',2'-disulfonic acid and influenced by the ATP analog 5'-fluorosulfonyl-benzoyladenosine. Comparing equimolar amounts of OppA in intact mycoplasma cells and in the purified form indicated that more than 80% of the surface-localized ATPase activity is derived from OppA, implying that OppA is the main ATPase on the surface of mycoplasma cells. Together, these data present the first evidence that the cytoadhesive substrate binding protein OppA of the oligopeptide permease also functions as an ecto-ATPase in Mycoplasma hominis.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas de Transporte/metabolismo , Lipoproteínas/metabolismo , Mycoplasma hominis/enzimologia , Trifosfato de Adenosina/metabolismo , Trifosfato de Adenosina/farmacologia , Proteínas de Bactérias , Subunidades Proteicas
10.
Antimicrob Agents Chemother ; 47(10): 3323-5, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14506049

RESUMO

Twelve clinical isolates of Ureaplasma spp. and one isolate of Mycoplasma hominis were examined for resistance to fluoroquinolones. Previously described mutations at positions 83 and 95 in GyrA (Escherichia coli numbering) and positions 80 and 87 in ParC were found. Unusual alterations were described at positions ParC 123 and 134.


Assuntos
DNA Girase/genética , DNA Topoisomerase IV/genética , Farmacorresistência Bacteriana/genética , Fluoroquinolonas/farmacologia , Mutação , Mycoplasma hominis/genética , Ureaplasma/genética , Adolescente , Adulto , Substituição de Aminoácidos , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mycoplasma hominis/efeitos dos fármacos , Mycoplasma hominis/enzimologia , Ureaplasma/efeitos dos fármacos , Ureaplasma/enzimologia
11.
Infect Dis Obstet Gynecol ; 9(1): 17-22, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11368254

RESUMO

OBJECTIVE: To determine the prevalence of Gardnerella vaginalis, anaerobic bacteria and Mycoplasma hominis in vaginal specimens of women with and without bacterial vaginosis (BV) as well as to determine the sensitivity and specificity of the direct sialidase assay of vaginal fluid as a rapid test for diagnosing this syndrome. METHODS: Vaginal cultures were obtained from 109 nonpregnant women (mean age 33 +/- 7.1 years), 47 of them with clinical signs of BV (BV+) and 62 of them without BV (BV-). In addition, we determined the vaginal sialidase activity in both groups, which may serve as a feature of this syndrome. RESULTS: Anaerobic bacteria were isolated in 91% and 18% of the BV+ and BV- groups, respectively (p < 0.001). Peptostreptococcus spp., Prevotella bivia and Porphyromonas spp. were strongly associated with BV. P. bivia and Prevotella spp. represented 44% of all the anaerobes isolated in the BV+ group. All the isolated P. bivia strains presented sialidase activity. G. vaginalis and M. hominis were isolated in 76% and 42% of the BV+ and 1% and 0% of the BV- women, respectively (p < 0.001). Mobiluncus morphotypes were observed in 34% of the BV+ and 0% of BV- women. Sensitivity, specificity, positive predictive value and negative predictive value of sialidase activity were 81%, 94%, 90% and 86%, respectively. CONCLUSIONS: Our data demonstrate a strong association between G. vaginalis, M. hominis, and P. bivia and BV. Sialidase activity and Gram stain of vaginal fluid represent accurate methods for diagnosing BV.


Assuntos
Gardnerella vaginalis/isolamento & purificação , Infecções por Mycoplasma/microbiologia , Mycoplasma hominis/isolamento & purificação , Neuraminidase/metabolismo , Vagina/microbiologia , Vaginose Bacteriana/microbiologia , Adulto , Bactérias Anaeróbias/enzimologia , Bactérias Anaeróbias/isolamento & purificação , Feminino , Gardnerella vaginalis/enzimologia , Humanos , Infecções por Mycoplasma/enzimologia , Mycoplasma hominis/enzimologia , Vagina/enzimologia , Vaginose Bacteriana/enzimologia
12.
FEMS Microbiol Lett ; 183(1): 15-21, 2000 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-10650196

RESUMO

The gap gene encodes the glycolytic enzyme glyceraldehyde 3-phosphate dehydrogenase (GAPDH). The gene was cloned and sequenced from the Mycoplasma hominis type strain PG21(T). The intraspecies variability was investigated by inspection of restriction fragment length polymorphism (RFLP) patterns after polymerase chain reaction (PCR) amplification of the gap gene from 15 strains and furthermore by sequencing of part of the gene in eight strains. The M. hominis gap gene was found to vary more than the Escherichia coli counterpart, but the variation at nucleotide level gave rise to only a few amino acid substitutions. To verify that the gene was expressed in M. hominis, a polyclonal antibody was produced and tested against whole cell protein from 15 strains. The enzyme was expressed in all strains investigated as a 36-kDa protein. All strains except type strain PG21(T) showed reaction to a 104-kDa band in addition to the expected 36-kDa band. The protein reacting at 104 kDa is a M. hominis protein with either an epitope similar to one on GAPDH, or it is an immunoglobulin binding protein.


Assuntos
Variação Genética , Gliceraldeído-3-Fosfato Desidrogenases/genética , Mycoplasma hominis/enzimologia , Mycoplasma hominis/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Southern Blotting , Mapeamento Cromossômico , Clonagem Molecular , Reações Cruzadas , Eletroforese em Gel de Poliacrilamida , Gliceraldeído-3-Fosfato Desidrogenases/química , Gliceraldeído-3-Fosfato Desidrogenases/imunologia , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Humanos , Dados de Sequência Molecular , Infecções por Mycoplasma/microbiologia , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Coelhos , Análise de Sequência de DNA
13.
Antimicrob Agents Chemother ; 43(10): 2493-6, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10508030

RESUMO

The role of mutations in the genes for GyrA and ParC in quinolone resistance in Mycoplasma hominis was studied. Selection with sparfloxacin gave mutations at GyrA83 (Ser-->Leu; Escherichia coli numbering) or GyrA87 (Glu-->Lys), and mutants had increased levels of resistance to sparfloxacin (8- to 16-fold) but not to ofloxacin. Selection with ofloxacin gave changes at ParC80 (Ser-->Ile) or ParC84 (Glu-->Lys), and mutants were four- to eightfold more resistant to ofloxacin but not to sparfloxacin. Selection of second-step mutants from strains with ParC mutations with either quinolone yielded double mutants with additional mutations at GyrA83 (Ser-->Trp or Ser-->Leu) or GyrA87 (Glu-->Lys). Second-step selection of GyrA mutants gave additional mutations at ParC80 (Ser-->Ile) or ParC84 (Glu-->Lys). Two-step mutants showed high levels of resistance to ofloxacin (MICs, 64 to 128 microg/ml) and moderate levels of resistance to sparfloxacin (MICs, 2 to 8 microg/ml). The primary target of ofloxacin in first-step mutants of Mycoplasma hominis was ParC, whereas that for sparfloxacin was GyrA.


Assuntos
Anti-Infecciosos/farmacologia , DNA Topoisomerases Tipo II/genética , Fluoroquinolonas , Mycoplasma hominis/efeitos dos fármacos , Ofloxacino/farmacologia , DNA Topoisomerase IV , Resistência Microbiana a Medicamentos/genética , Mycoplasma hominis/enzimologia , Mycoplasma hominis/genética , Mutação Puntual
14.
J Perinat Med ; 26(3): 208-10, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9773381

RESUMO

The clinical relevance of vaginal colonization with Mycoplasma hominis (M hominis) as a cause of prematurity is doubtful. One of the possible pathways which could explain the role of M hominis in the induction of preterm labour is an increased synthesis of prostaglandins by a phospholipase A2 activity. The aim of this study was to prove whether M hominis secrets proteins with a PLA2 activity and to test whether there are strain differences in the enzyme activity between M hominis isolated from women with normal pregnancy and those with preterm labour. Using specific radio-immunoassay we could not measure any PLA2 activity in the supernatant of all investigated M hominis strains. We exclude the mechanism of induction of preterm labour by M hominis via an increased prostaglandin synthesis. Our findings make a relation between vaginal colonization with M hominis and prematurity unlikely.


Assuntos
Doenças dos Genitais Femininos/microbiologia , Mycoplasma hominis/enzimologia , Trabalho de Parto Prematuro/microbiologia , Fosfolipases A/análise , Complicações Infecciosas na Gravidez/microbiologia , Feminino , Humanos , Fosfolipases A2 , Gravidez , Especificidade da Espécie
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