Maire Peters | University of Tartu (original) (raw)

Papers by Maire Peters

Research paper thumbnail of Features of the Replicon of Plasmid pAM10.6 of Pseudomonas fluorescens

Research paper thumbnail of Organization of the horizontally transferred pheBA operon and its adjacent genes in the genomes of eight indigenous Pseudomonas strains

Plasmid, 2004

Horizontal transfer of genes encoding phenol degradation (pheBA) in the environment has been prev... more Horizontal transfer of genes encoding phenol degradation (pheBA) in the environment has been previously described. Complete or partial phe-operon was redetected in plasmids of several indigenous Pseudomonas strains isolated from the river water. The sequences of up- and downstream regions of the acquired phe-DNA in eight different plasmids were analyzed. In all cases, miniature insertional elements or putative transposase genes were found suggesting transposase dependent pheBA integration into plasmids. In three cases, an open reading frame encoding homologue to the transcription regulator protein (CatR) of the pheBA operon was determined.

Research paper thumbnail of Plasmid-encoded catalase KatA, the main catalase of Pseudomonas fluorescens strain Cb36

Fems Microbiology Letters, 2001

Research paper thumbnail of Acquisition of a Deliberately Introduced Phenol Degradation Operon, pheBA, by Different Indigenous Pseudomonas Species

Research paper thumbnail of Plasmid-encoded catalase KatA, the main catalase of Pseudomonas fluorescens strain Cb36

Fems Microbiology Letters, 2001

The plasmid-state catalase gene katA of the phenol gradative Pseudomonas fluorescens isolate Cb36... more The plasmid-state catalase gene katA of the phenol gradative Pseudomonas fluorescens isolate Cb36 has been characterized and shown to be the major catalase of this strain. The predicted amino acid sequence of KatA revealed significant similarity with the catalase sequence from Neisseria meningitidis and has probably the non-pseudomonad origin. The specific activity of catalase was investigated and elevated catalase activity was found in stationary phase cells. The consensus sequence for promoters recognized by the stationary phase sigma factor σs was found 212 bp upstream of the putative ATG start codon. The ability of KatA to detoxify a high concentration of hydrogen peroxide and protect Pseudomonas putida and Escherichia coli cells was shown.

Research paper thumbnail of Monitoring of Biodegradative Pseudomonas putida Strains in Aquatic Environments Using Molecular Techniques

Microbial Ecology, 1997

Monitoring strategies were developed to track non–genetically engineered Pseudomonas putida strai... more Monitoring strategies were developed to track non–genetically engineered Pseudomonas putida strains in the open environment. The strain E1 was used for four years for the biodegradation of phenolic compounds in industrial wastewater in Põlva, Estonia. In this study we used the strain E2 which is a non-carbenicillin-resistant variant of the strain E1. Both strains have a deletion of approximately 34 kb in the TOL plasmid pWW0 which served as a basis for discrimination from indigenous bacteria by molecular analyses. Other targets used for PCR and DNA hybridization were the xylE gene and a sequence located in the left-handed region of to the transposon Tn4652. In laboratory tests we demonstrated that two cells inoculated into 20 ml of river water could be detected against a background of more than 107 colony forming units (CFUs) by a combination of growth on selective media and molecular analysis. Using the same combination of methods in a deliberate release experiment, detection of the released strain was possible only to 32 h after release. It is assumed that the released strains did not survive in the aquatic ecosystem, mainly due to the high dilution rate. The combination of cultivation on selective media and molecular analyses proved useful for tracking Pseudomonas putida strain E2 in an aquatic environment.

Research paper thumbnail of The contribution of genetic variations of aryl hydrocarbon receptor pathway genes to male factor infertility

Fertility and Sterility, 2007

Research paper thumbnail of VNTR I/I genotype of insulin gene is associated with the increase of follicle number independent from polycystic ovary syndrome

Acta Obstetricia Et Gynecologica Scandinavica, 2007

Polycystic ovary syndrome (PCOS) is accompanied by selective insulin resistance and enhanced ovar... more Polycystic ovary syndrome (PCOS) is accompanied by selective insulin resistance and enhanced ovarian steroidogenic effects of insulin. We analysed the minisatellite variations of the insulin gene (INS VNTR) with regard to the clinical features of PCOS. Retrospective, adjusted association study. Infertile patients with PCOS (n=30) and tubal factor (n=75) were screened for anthropometrical, clinical and ovarian morphology parameters, as well as hormonal values. INS VNTR was genotyped by its surrogate marker at -23 HphI locus. INS VNTR genotype distribution was similar in PCOS and tubal infertility group. The mean ovarian follicle number was higher in VNTR I/I individuals compared to VNTR I/III and III/III individuals (adjusted OR=1.28, p=0.03), independent from the cause of infertility, the age, the follicle stimulating hormone level on day 3-5 of menstrual cycle, BMI and the previous surgical ovarian tissue removal. In addition, higher level of the luteinising hormone in VNTR I/I individuals was associated with the increase in follicle number. We suggest that INS VNTR genotypes are not associated with PCOS in general, but could have a certain influence on the phenotypic spectrum of the syndrome.

Research paper thumbnail of Analysis of polymorphisms in the SRD5A2 gene and semen parameters in Estonian men

Research paper thumbnail of Incontinentia pigmenti in a female conceived by in vitro fertilization

American Journal of Medical Genetics Part A, 2008

Research paper thumbnail of Association of CCR5, TLR2, TLR4 and MBL genetic variations with genital tract infections and tubal factor infertility

Journal of Reproductive Immunology, 2010

Research paper thumbnail of Cytogenetic and molecular characterization of the derivative Y chromosome: a case study of an azoospermic patient

Research paper thumbnail of Mannose-binding lectin genotypes: potential role in tubal damage and adverse IVF outcome

Journal of Reproductive Immunology

The innate immune system provides the first-line defence against genital tract pathogens and is a... more The innate immune system provides the first-line defence against genital tract pathogens and is also involved in establishing and maintaining a successful pregnancy. Genetic variation of factors regulating immune response can be associated with complications after genital tract infections and may lead to unfavourable pregnancy outcomes. This study focused on four polymorphisms in the mannose binding lectin gene (MBL2) and assessed their significance in tubal damage and female fertility by comparing genotype frequencies among 388 controls and women with tubal factor infertility (n=155) or previous ectopic pregnancy (n=178). The high-producing MBL2 genotype HYA/LYA was found to have a protective effect, while the hyper-producing MBL2 genotype HYA/HYA and low-producing MBL2 genotypes were associated with susceptibility to tubal factor infertility. Also, the low-producing genotypes showed association with early pregnancy loss in IVF treatment. In conclusion, these data suggest that certain MBL2 genotypes can be associated with tubal damage in patients with evidence of Chlamydia trachomatis infection and additionally may contribute to the pathogenesis of early pregnancy loss.

Research paper thumbnail of Androgen receptor gene haplotype is associated with male infertility

Research paper thumbnail of Genetic variations in vascular endothelial growth factor but not in angiotensin I-converting enzyme genes are associated with endometriosis in Estonian women

European Journal of Obstetrics & Gynecology and Reproductive Biology, 2010

Research paper thumbnail of Polymorphisms in MMP-2 and MMP-9 promoter regions are associated with endometriosis

Fertility and Sterility, 2010

Research paper thumbnail of Androgen receptor gene haplotype is associated with male infertility

International Journal of Andrology, 2008

The purpose of the current study was to evaluate the importance of androgen receptor (AR) gene ha... more The purpose of the current study was to evaluate the importance of androgen receptor (AR) gene haplotypes and polymorphic CAG/GGN microsatellites in the aetiology of male infertility. We genotyped six haplotype-tagging single nucleotide polymorphisms and CAG/GGN microsatellites of the AR gene in 112 infertile and 212 control Estonian men. A total of 13 AR haplotypes (HAP1–13) were identified, among which HAP4 was found to confer increased risk for male infertility (OR = 5.15, 95% CI = 1.75–15.15, p = 0.003). However, infertile patients and controls had similar lengths and distributions of both AR CAG (mean ± SD number of repeats 21.1 ± 2.5 vs. 21.2 ± 2.3, respectively) and GGN (mean ± SD number of repeats 22.5 ± 1.5 vs. 22.4 ± 1.9, respectively) repeats. In addition, HAP2 was associated with more CAG repeats (r = 1.17, p = 0.033) and HAP3 with fewer CAG repeats (r = −2.93, p < 0.001) than the major haplotype HAP1. HAP3 and HAP4 were associated with more GGN repeats (r = 1.35, p = 0.001 and r = 1.36, p = 0.002, respectively) than HAP1. In conclusion, our results implicated the AR-HAP4 gene haplotype in increased risk for male infertility, while no association was found between AR CAG/GGN microsatellites and impaired spermatogenesis.

Research paper thumbnail of Follicle-Stimulating Hormone Receptor Gene Haplotypes and Male Infertility in Estonian Population and Meta-Analysis

Systems Biology in Reproductive Medicine, 2010

Research paper thumbnail of Research Letter Incontinentia Pigmenti in a Female Conceived by In Vitro Fertilization

Research paper thumbnail of Fetal trisomy 13 and 21 mosaicism diagnosed at amniocentesis: a case report

Research paper thumbnail of Features of the Replicon of Plasmid pAM10.6 of Pseudomonas fluorescens

Research paper thumbnail of Organization of the horizontally transferred pheBA operon and its adjacent genes in the genomes of eight indigenous Pseudomonas strains

Plasmid, 2004

Horizontal transfer of genes encoding phenol degradation (pheBA) in the environment has been prev... more Horizontal transfer of genes encoding phenol degradation (pheBA) in the environment has been previously described. Complete or partial phe-operon was redetected in plasmids of several indigenous Pseudomonas strains isolated from the river water. The sequences of up- and downstream regions of the acquired phe-DNA in eight different plasmids were analyzed. In all cases, miniature insertional elements or putative transposase genes were found suggesting transposase dependent pheBA integration into plasmids. In three cases, an open reading frame encoding homologue to the transcription regulator protein (CatR) of the pheBA operon was determined.

Research paper thumbnail of Plasmid-encoded catalase KatA, the main catalase of Pseudomonas fluorescens strain Cb36

Fems Microbiology Letters, 2001

Research paper thumbnail of Acquisition of a Deliberately Introduced Phenol Degradation Operon, pheBA, by Different Indigenous Pseudomonas Species

Research paper thumbnail of Plasmid-encoded catalase KatA, the main catalase of Pseudomonas fluorescens strain Cb36

Fems Microbiology Letters, 2001

The plasmid-state catalase gene katA of the phenol gradative Pseudomonas fluorescens isolate Cb36... more The plasmid-state catalase gene katA of the phenol gradative Pseudomonas fluorescens isolate Cb36 has been characterized and shown to be the major catalase of this strain. The predicted amino acid sequence of KatA revealed significant similarity with the catalase sequence from Neisseria meningitidis and has probably the non-pseudomonad origin. The specific activity of catalase was investigated and elevated catalase activity was found in stationary phase cells. The consensus sequence for promoters recognized by the stationary phase sigma factor σs was found 212 bp upstream of the putative ATG start codon. The ability of KatA to detoxify a high concentration of hydrogen peroxide and protect Pseudomonas putida and Escherichia coli cells was shown.

Research paper thumbnail of Monitoring of Biodegradative Pseudomonas putida Strains in Aquatic Environments Using Molecular Techniques

Microbial Ecology, 1997

Monitoring strategies were developed to track non–genetically engineered Pseudomonas putida strai... more Monitoring strategies were developed to track non–genetically engineered Pseudomonas putida strains in the open environment. The strain E1 was used for four years for the biodegradation of phenolic compounds in industrial wastewater in Põlva, Estonia. In this study we used the strain E2 which is a non-carbenicillin-resistant variant of the strain E1. Both strains have a deletion of approximately 34 kb in the TOL plasmid pWW0 which served as a basis for discrimination from indigenous bacteria by molecular analyses. Other targets used for PCR and DNA hybridization were the xylE gene and a sequence located in the left-handed region of to the transposon Tn4652. In laboratory tests we demonstrated that two cells inoculated into 20 ml of river water could be detected against a background of more than 107 colony forming units (CFUs) by a combination of growth on selective media and molecular analysis. Using the same combination of methods in a deliberate release experiment, detection of the released strain was possible only to 32 h after release. It is assumed that the released strains did not survive in the aquatic ecosystem, mainly due to the high dilution rate. The combination of cultivation on selective media and molecular analyses proved useful for tracking Pseudomonas putida strain E2 in an aquatic environment.

Research paper thumbnail of The contribution of genetic variations of aryl hydrocarbon receptor pathway genes to male factor infertility

Fertility and Sterility, 2007

Research paper thumbnail of VNTR I/I genotype of insulin gene is associated with the increase of follicle number independent from polycystic ovary syndrome

Acta Obstetricia Et Gynecologica Scandinavica, 2007

Polycystic ovary syndrome (PCOS) is accompanied by selective insulin resistance and enhanced ovar... more Polycystic ovary syndrome (PCOS) is accompanied by selective insulin resistance and enhanced ovarian steroidogenic effects of insulin. We analysed the minisatellite variations of the insulin gene (INS VNTR) with regard to the clinical features of PCOS. Retrospective, adjusted association study. Infertile patients with PCOS (n=30) and tubal factor (n=75) were screened for anthropometrical, clinical and ovarian morphology parameters, as well as hormonal values. INS VNTR was genotyped by its surrogate marker at -23 HphI locus. INS VNTR genotype distribution was similar in PCOS and tubal infertility group. The mean ovarian follicle number was higher in VNTR I/I individuals compared to VNTR I/III and III/III individuals (adjusted OR=1.28, p=0.03), independent from the cause of infertility, the age, the follicle stimulating hormone level on day 3-5 of menstrual cycle, BMI and the previous surgical ovarian tissue removal. In addition, higher level of the luteinising hormone in VNTR I/I individuals was associated with the increase in follicle number. We suggest that INS VNTR genotypes are not associated with PCOS in general, but could have a certain influence on the phenotypic spectrum of the syndrome.

Research paper thumbnail of Analysis of polymorphisms in the SRD5A2 gene and semen parameters in Estonian men

Research paper thumbnail of Incontinentia pigmenti in a female conceived by in vitro fertilization

American Journal of Medical Genetics Part A, 2008

Research paper thumbnail of Association of CCR5, TLR2, TLR4 and MBL genetic variations with genital tract infections and tubal factor infertility

Journal of Reproductive Immunology, 2010

Research paper thumbnail of Cytogenetic and molecular characterization of the derivative Y chromosome: a case study of an azoospermic patient

Research paper thumbnail of Mannose-binding lectin genotypes: potential role in tubal damage and adverse IVF outcome

Journal of Reproductive Immunology

The innate immune system provides the first-line defence against genital tract pathogens and is a... more The innate immune system provides the first-line defence against genital tract pathogens and is also involved in establishing and maintaining a successful pregnancy. Genetic variation of factors regulating immune response can be associated with complications after genital tract infections and may lead to unfavourable pregnancy outcomes. This study focused on four polymorphisms in the mannose binding lectin gene (MBL2) and assessed their significance in tubal damage and female fertility by comparing genotype frequencies among 388 controls and women with tubal factor infertility (n=155) or previous ectopic pregnancy (n=178). The high-producing MBL2 genotype HYA/LYA was found to have a protective effect, while the hyper-producing MBL2 genotype HYA/HYA and low-producing MBL2 genotypes were associated with susceptibility to tubal factor infertility. Also, the low-producing genotypes showed association with early pregnancy loss in IVF treatment. In conclusion, these data suggest that certain MBL2 genotypes can be associated with tubal damage in patients with evidence of Chlamydia trachomatis infection and additionally may contribute to the pathogenesis of early pregnancy loss.

Research paper thumbnail of Androgen receptor gene haplotype is associated with male infertility

Research paper thumbnail of Genetic variations in vascular endothelial growth factor but not in angiotensin I-converting enzyme genes are associated with endometriosis in Estonian women

European Journal of Obstetrics & Gynecology and Reproductive Biology, 2010

Research paper thumbnail of Polymorphisms in MMP-2 and MMP-9 promoter regions are associated with endometriosis

Fertility and Sterility, 2010

Research paper thumbnail of Androgen receptor gene haplotype is associated with male infertility

International Journal of Andrology, 2008

The purpose of the current study was to evaluate the importance of androgen receptor (AR) gene ha... more The purpose of the current study was to evaluate the importance of androgen receptor (AR) gene haplotypes and polymorphic CAG/GGN microsatellites in the aetiology of male infertility. We genotyped six haplotype-tagging single nucleotide polymorphisms and CAG/GGN microsatellites of the AR gene in 112 infertile and 212 control Estonian men. A total of 13 AR haplotypes (HAP1–13) were identified, among which HAP4 was found to confer increased risk for male infertility (OR = 5.15, 95% CI = 1.75–15.15, p = 0.003). However, infertile patients and controls had similar lengths and distributions of both AR CAG (mean ± SD number of repeats 21.1 ± 2.5 vs. 21.2 ± 2.3, respectively) and GGN (mean ± SD number of repeats 22.5 ± 1.5 vs. 22.4 ± 1.9, respectively) repeats. In addition, HAP2 was associated with more CAG repeats (r = 1.17, p = 0.033) and HAP3 with fewer CAG repeats (r = −2.93, p < 0.001) than the major haplotype HAP1. HAP3 and HAP4 were associated with more GGN repeats (r = 1.35, p = 0.001 and r = 1.36, p = 0.002, respectively) than HAP1. In conclusion, our results implicated the AR-HAP4 gene haplotype in increased risk for male infertility, while no association was found between AR CAG/GGN microsatellites and impaired spermatogenesis.

Research paper thumbnail of Follicle-Stimulating Hormone Receptor Gene Haplotypes and Male Infertility in Estonian Population and Meta-Analysis

Systems Biology in Reproductive Medicine, 2010

Research paper thumbnail of Research Letter Incontinentia Pigmenti in a Female Conceived by In Vitro Fertilization

Research paper thumbnail of Fetal trisomy 13 and 21 mosaicism diagnosed at amniocentesis: a case report