مقالات پذیرفته شده در پنجمین کنگره بین المللی زیست پزشکی
Distribution of Virulence Genes of Streptococcus agalactiae isolated from Pregnant Women in Bushehr
Distribution of Virulence Genes of Streptococcus agalactiae isolated from Pregnant Women in Bushehr
Somayyeh Gharibi,1,*Mahnaz Gholipour shahrak,2Fahimeh Tavakoli,3Saeed Tajbakhsh,4Abbas Yadegar,5Zeinab Asen,6
1. Department of Microbiology, School of Sciences, Kherad Institute of Higher Education, Bushehr, Iran 2. Department of Microbiology, School of Sciences, Kherad Institute of Higher Education, Bushehr, Iran 3. Department of Microbiology, School of Sciences, Kherad Institute of Higher Education, Bushehr, Iran 4. Department of Microbiology and Parasitology, School of Medicine, Bushehr University of Medical Sciences, Bushehr, Iran 5. Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran. 6. Department of Microbiology, School of Sciences, Kherad Institute of Higher Education, Bushehr, Iran
Introduction: Streptococcus agalactiae, GBS, is an important pathogen in neonates and
pregnant women that normally colonizes the vagina and opportunistically leads to invasive
diseases. GBS included several pathogenic genes that expression is directly involved in the
prognosis of disease, bacterial survival and invasion. The aim of this study was to evaluate the
frequency of group B streptococcal pathogenesis genes by PCR in pregnant women in Bushehr.
Material and Methods: In this cross-sectional descriptive study, 25 GBS-positive samples
isolated from pregnant women aged 35-42 weeks of pregnancy were studied. After DNA
extraction and ensuring its purity, PI-1, PI-2a, PI-2b, PGi, fbsB, lmb and scpB genes were
examined through specific primers.
Methods: In this study, 25 GBS-positive samples
isolated from pregnant women aged 35-42 weeks of pregnancy were studied. After DNA
extraction and ensuring its purity, They were confirmed by a housekeeping gene primer, pgi by PCR, and then PI-1, PI-2a, PI-2b, fbsB, lmb and scpB genes were
examined through specific primers.
Results: The presence of pgi gene as housekeeping gene was confirmed in all strains. The sCpB gene was positive in 9 samples (36%). PI-1, PI-2a and PI-2b genes were
found in 19 samples (76%), 1 sample (4%) and 1 sample (4%), respectively. The prevalence of
fbsB was positive in 100% of the samples and the prevalence of lmb was positive in 92% of the
isolates. 17 samples (68%) had at least one type of PI-1 cell. In one case (4%) there was a
combination of PI-1 / PI-2b and in one case (4%) there was a combination of PI-1 / PI-2a, while
5 samples (20%) did not have any pilus genes. In 4 samples (16%) there were 4 pathogens and
in 2 cases (8%) there were 5 sCpB / PI-1 / PI-2a / fbsB / lmb factors (except PGi). 15 cases
(60%) carried 3 pathogens. The predominant gene profile was PI-1 /lmb / fbsB with a prevalence
of 76%. The scpB+lmb interaction was seen in 36% of the strains.
Conclusion: This study showed that the prevalence of virulence genes among the existing
strains is highly variable. However, the isolates evaluated in it may contain other known and
unknown virulence genes. These genes may also be expressed differently in various populations.
That is why more research needs to be done on the prevalence of more virulence genes in more
pregnant women.