Vaginal Strains Research Articles

Probiotics: The Potential for a Live Microbicide to Prevent HIV

After early microbicide candidates failed in clinical trials to prevent HIV, recent news from the South African CAPRISA-004 study suggest that the new generation of vaginal microbicide gels using antiretroviral drugs like tenofovir could be effective and reduce HIV and herpes simplex virus (HSV)-2 acquisition.1 This landmark study greatly energized the field and revived enthusiasm for the development of female-controlled products to prevent HIV acquisition in women, and if ongoing trials confirm the CAPRISA-004 results lead to a licensed product by 2014. 2,3 While the field is getting closer to identifying an effective compound against vaginal HIV transmission, significant challenges remain, such as a sustained coitally-independent release of an effective drug, and a product formulation and administration that suits life circumstances of women in developing countries. Stigma continues to limit women’s access to HIV prevention strategies, and many women underestimate their own risk of HIV infection4. Thus, a microbicide product perceived to improve overall vaginal health may decrease possible acceptability barriers that a single purpose product associated with HIV prevention may face. In late May, the bi-annual global conference Microbicides 2010 held in Pittsburgh (USA) was attended by 1000 scientists and advocates, including more than 300 from Africa. The UCSF Bixby Center for Global Reproductive Health and the Consortium to Advance Multipurpose Innovations (CAMI) organized a Satellite Symposium titled ‘Probiotics: the Potential for a Live Microbicide’. The event provided a platform for researchers working in related fields to educate the conference audience and to initiate a discussion with other scientists, donors, advocates, members of federal agencies and world bodies, and regulatory experts in order to accelerate the development of probiotics for HIV prevention. A handful of small biotechnology companies and academic groups are working to develop a new generation of genetically enhanced probiotics by inserting genes which code for potent antiviral compounds into bacteria that naturally colonize the vagina. Once administered to the vagina, these next generation probiotics have the potential to serve as a sustained, self-replicating delivery system for antimicrobial compounds to combat reproductive tract infections, including HIV. The potential advantages of a probiotic microbicide continuously producing anti- HIV protein compounds in situ over conventional microbicide delivery systems such as gels and films include: i) periodic, possibly weekly or monthly replenishment vs. coitally dependent or daily dosing; ii) minimal disposal concerns, e.g. applicators; and iii) low-risk of developing HIV resistance in comparison to antiretroviral therapy commonly used in treatment, such as tenofovir. However, the field to date has been hampered by a relative lack of interest among donors due to competing HIV prevention technologies under development, lack of clarity regarding the regulatory pathway for licensure and general sensitivity surrounding genetically modified organisms (GMO), and financial fall-out from the recent worldwide recession.

Lactobacilli isolated from vaginal vault of dairy and meat cows during progesteronic stage of estrous cycle

Lactobacilli have been barely studied in cows. We proposed isolate and characterize lactic acid bacteria from dairy cows as compared to those raised for meat production and elucidate the presence of strains with evident probiotic employment’s potential. For this, isolation and quantification of LAB mainly lactobacilli were realized from vaginal cattle samples in MRS medium. Each selected microorganism was then briefly characterized. The MATH method was employed using hexadecane, xilene an toluene as solvent. According to the hydrophobic characteristics, strains were classified into three categories: high (71–100%), medium (36–70%) and low (0–35%). Hydrogen peroxide qualitative production was studies too, lactobacilli were streaked onto an MRS agar plate containing 5 mg of 3,3′,5,5′-tetramethylbenzidine and 0.20 mg of horseradish peroxidase. Twenty-one sampled cows (78%) were positive for lactic acid microflora, 12 belonging to the dairy group and 17 of the meat group. Total LAB counting including dairy and meat cows were log 2,41 CFU/ml. Of overall identified strains, an 83% corresponded to lactobacilli. Most strains belonged to the heterofermentative facultative group (75%), with L. plantarum as the most frequent specie. The highest proportion of isolated vaginal strains (69%) had low hydrophobicity, the LAB with highest hydrophobic characteristics (3 strains) were found only in meat cows. In the qualitative evaluation of H 2O 2 production, a positive reaction was observed in 13 of 29 strains (45%). The role of lactobacilli in vaginal microbiota is limited, and therefore the present work is interesting in incorporate knowledge of normal microflora of progesteronic healthy cows, in this case in production animals. The isolation and characterization data obtained are consistent in consider the study of particular strains with great potential in the development of a probiotic for production cows.

Induction, structural characterization, and genome sequence of Lv1, a prophage from a human vaginal Lactobacillus jensenii strain

The prophage Lv1, harbored by a vaginal Lactobacillus jensenii isolate, was induced by several different anticancer, antimicrobial, and antiseptic agents, suggesting that they contribute to the adverse vaginal effects associated with their therapeutic use. Of special interest with respect to its novelty was the inducing effect of nonoxynol-9, a non-ionic detergent commonly used as a spermicide. The Lv1 genome consists of a 38,934-bp dsDNA molecule with cohesive ends, in which 48 ORFs were recognized, and is organized into functional modules. Lv1 belongs to the family Siphoviridae and, more precisely, to the proposed Sfi21-like genus. The capsid-tail junction of the Lv1 virions is fragile such that most particles become disrupted, suggesting that the virus is defective and thus unable to generate fertile progeny. However, genome analysis did not provide evidence of the defective nature of the prophage, other than the finding that its genome is shorter than those of other, related, phages. Further analysis indicated that prophage Lv1 suffered deletions in its right half to the extent that it no longer fulfill the minimum packaging limits, thereby generating the observed unstable particles.

Antifungal Activity of Propolis Extract Against Yeasts Isolated from Vaginal Exudates

The objective of this study was to evaluate the in vitro antifungal activity of propolis extract against yeasts Candida albicans and Candida non-albicans isolated from vaginal exudates, in comparison with nystatin. Ninety-seven (97) vaginal yeasts strains were evaluated. These strains were obtained from different clinical conditions, isolated and stored at the Sector of Medical Mycology of the State University of Maringá (Paraná, Brazil). The assays of susceptibility to nystatin and propolis extracts (PE) were conducted through microdilution in broth (National Committee for Clinical Laboratory Standards-NCCLS, M-27A Document of 1997). All the yeasts tested were inhibited by low concentrations of PE (maximum of 393.19 mug/mL of the total flavonoid content), including an isolate resistant to nystatin, regardless of the clinical conditions of the women and the species of yeast isolated. The PE showed an outstanding performance against the tested vaginal yeast strains, and could be included among the novel therapeutic options for the treatment of vulvovaginal candidiasis.

Individual and co-operative roles of lactic acid and hydrogen peroxide in the killing activity of enteric strain Lactobacillus johnsonii NCC933 and vaginal strain Lactobacillus gasseri KS120.1 against enteric, uropathogenic and vaginosis-associated pathog

The mechanism underlying the killing activity of Lactobacillus strains against bacterial pathogens appears to be multifactorial. Here, we investigate the respective contributions of hydrogen peroxide and lactic acid in killing bacterial pathogens associated with the human vagina, urinary tract or intestine by two hydrogen peroxide-producing strains. In co-culture, the human intestinal strain Lactobacillus johnsonii NCC933 and human vaginal strain Lactobacillus gasseri KS120.1 strains killed enteric Salmonella enterica serovar Typhimurium SL1344, vaginal Gardnerella vaginalis DSM 4944 and urinary tract Escherichia coli CFT073 pathogens. The cell-free culture supernatants (CFCSs) produced the same reduction in SL1344, DSM 4944 and CFT073 viability, whereas isolated bacteria had no effect. The killing activity of CFCSs was heat-stable. In the presence of Dulbecco's modified Eagle's minimum essential medium inhibiting the lactic acid-dependent killing activity, CFCSs were less effective at killing of the pathogens. Catalase-treated CFCSs displayed a strong decreased activity. Tested alone, hydrogen peroxide triggered a concentration-dependent killing activity against all three pathogens. Lactic acid alone developed a killing activity only at concentrations higher than that present in CFCSs. In the presence of lactic acid at a concentration present in Lactobacillus CFCSs, hydrogen peroxide displayed enhanced killing activity. Collectively, these results demonstrate that for hydrogen peroxide-producing Lactobacillus strains, the main metabolites of Lactobacillus, lactic acid and hydrogen peroxide, act co-operatively to kill enteric, vaginosis-associated and uropathogenic pathogens.

Influence of carbohydrates on cell properties of Lactobacillus rhamnosus

AbstractLactobacilli represent normal commensals of the human body, particularly in the gut and vagina where they protect these environments from incoming pathogens via a variety of mechanisms. The influence of the carbohydrate source present in reconstituted MRS growth medium on the different cell properties of two Lactobacillus rhamnosus strains were examined. Two human vaginal isolates, BGHV719 and exopolysaccharide producer strain BGHV954 were analyzed. The results demonstrated that unlike in reconstituted MRS with glucose as a carbon source, the presence of fructose, mannose, or rhamnose, significantly reduced cell surface hydrophobicity of both strains. In addition, differences in cell wall protein composition of L. rhamnosus BGHV719 and alterations in colony mucoidity of L. rhamnosus BGHV954 were also demonstrated. Light and SEM microscopy revealed differences on the cellular level when BGHV719 was cultivated in the presence of different sugars. The results of this study point out the importance of complex relationships between growth medium composition and the different aspects of bacterial behavior, and call for more detailed analyses of versatile bacterial responses to the changes in the environment, including vaginal ecosystem. This is especially important since lactobacilli are amongst the most widely used of probiotics.

Stability of freeze-dried vaginalLactobacillusstrains in the presence of different lyoprotectors

The industrial use of lactic acid bacteria as probiotic cultures depends on the preservation techniques employed, which are required to guarantee stable cultures in terms of viability and functional activity. The aim of this study was to evaluate the effects of 12% lactose and 12% sucrose suspended in water or reconstituted skim milk on the survival and expression of beneficial characteristics during freeze-drying and subsequent storage of 6 vaginal lactobacilli strains. A cubic polynomial model was also used for the first time to evaluate the effects of different protectors on survival behavior during storage. Different survival patterns were observed among the strains considered. The presence of both lactose and sucrose in water or in 6% skim milk as the suspension medium proved to be effective in maintaining a high degree of survival and expression of potentially probiotic characteristics (production of antimicrobial substances or auto-aggregation capabilities) of most strains after lyophilization and long-term storage. This study constitutes a valuable step to obtain concentrated cultures with the highest stability of microorganisms for pharmaceutical purposes.

Genetic diversity of Streptococcus agalactiae strains and density of vaginal carriage

We screened 500 pregnant women who had no risk factors for Streptococcus agalactiae vaginal carriage, and isolated 39 S. agalactiae strains (8 %). The density of carriage was low in 16 cases (41 %), intermediate in 16 cases (41 %) and heavy in seven cases (18 %). Strains were mostly of serotype III (41 %), Ia (26 %) and V (18 %). Thirty-five strains had at least one of five genetic markers that have been associated with virulent phylogenetic subgroups of strains. Using PCR, nine strains (23 %) were identified as belonging to CC17. The 39 vaginal strains that were studied exhibited a substantial genetic diversity; there were 39 PFGE profiles and 13 variants defined on the basis of the five genetic markers studied. The prevalence of the studied genetic characteristics was similar for strains associated with all three classes of density of carriage. These data suggest that genetic features that are markers of S. agalactiae strains able to invade the central nervous system of neonates are not determinants for vaginal adaptation.

Spray Drying of a Vaginal Probiotic Strain of Lactobacillus acidophilus

This work presents a study of the spray-drying process of a vaginal strain of Lactobacillus acidophilus in order to enhance the cells viability and probiotics properties during storage. The results show that the powder obtained presents dried strain viability in the range of 108–109 (CFU/g) with product moisture content below 10%. Additionally, the dehydrated strain maintains its viability during two months when stored at 4°C, although its viability drops 1 order of magnitude when stored at 25°C for 1 month. It was verified that the range of operating conditions studied during drying (e.g., pressure, feed concentration, and additive) did not affect bacteria viability, except for increased air-drying temperature. The strain did not suffer important changes in its identity, morphology, or probiotic properties due to the spray-drying process. Using the mass-energy balance in the dryer, the volumetric overall heat transfer coefficient was determined as 2 × 10−4 (kg water evaporated/m3 K s) for the experimental drying system.

Inhibitory Activity of Vaginal Lactobacilli Against Human Pathogens

ABSTRACTLactic acid bacteria have long been considered as protective microflora, able to displace and kill different pathogens. Twenty vaginal strains, pre-selected as probiotics, were additionally characterized as effective antagonists against human pathogens. Four clinical reference strains- Staphylococcus aureus ATCC 25923, Staphylococcus aureus (MRSA) ATCC 39592, Pseudomonas aeruginosa ATCC 27853 and E. coli ATCC 25922 were used as test-cultures in initial screening procedure. The active strains belonging to the species L. fermentum, L. gasseri and L. salivarius were tested against 10 antibiotic-resistant and problematic clinical isolates. In vitro the growth inhibition of two Acinetobacter baumannii and two Pseudomonas aeruginosa out-patient strains was observed. The active antimicrobials were the lactic acid and hydrogen peroxid produced during the cultivation of ten vaginal strains, in combination with termo and proteinase- sensitive bacteriocin-like metabolites. Our results provide a promising base for further characterization of active compounds synthesized from Bulgarian vaginal Lactobacillus strains.

Engineering of a Human Vaginal Lactobacillus Strain for Surface Expression of Two-Domain CD4 Molecules

Women are at significant risk of heterosexually transmitted human immunodeficiency virus (HIV) infection, with the mucosal epithelium of the cervix and vagina serving as a major portal of entry. The cervicovaginal mucosa naturally harbors dynamic microflora composed predominantly of lactobacilli, which may be genetically modified to serve as a more efficient protective barrier against the heterosexual transmission of HIV. We selected a vaginal strain of Lactobacillus, L. jensenii 1153, for genetic modification to display surface-anchored anti-HIV proteins. Genomic sequencing analyses revealed that L. jensenii 1153 encodes several unique high-molecular-weight cell wall-anchored proteins with a C-terminal cell wall sorting LPQTG motif. In this report, we employed these proteins to express a surface-anchored two-domain CD4 (2D CD4) molecule in L. jensenii 1153. Our studies indicated that the C-terminal cell wall sorting signal LPQTG motif alone is insufficient to drive the surface expression of heterologous proteins, and the display of surface-anchored 2D CD4 molecules required native sequences of a defined length upstream of the unique C-terminal LPQTG cell wall sorting signal and the positively charged C terminus in a Lactobacillus-based expression system. The modified L. jensenii strain displayed 2D CD4 molecules that were uniformly distributed on bacterial surfaces. The surface-anchored 2D CD4 molecule was recognized by a conformation-dependent anti-CD4 antibody, suggesting that the expressed proteins adopted a native conformation. The establishment of this Lactobacillus-based surface expression system, with potential broad applicability, represents a major step toward developing an inexpensive yet durable approach to topical microbicides for the mitigation of heterosexual transmission of HIV and other mucosally transmitted viral pathogens.

Purification and characterization of enterocin 62-6, a two-peptide bacteriocin produced by a vaginal strain ofEnterococcus faecium: Potential significance in bacterial vaginosis

Purification and characterization of enterocin 62-6, a two-peptide bacteriocin produced by a vaginal strain of<i>Enterococcus faecium</i>: Potential significance in bacterial vaginosis

Diversity of the Lactobacillus group in breast milk and vagina of healthy women and potential role in the colonization of the infant gut

To evaluate the diversity of the Lactobacillus group in breast milk and the vagina of healthy women and understand their potential role in the infant gut colonization using the 16S rRNA gene approaches. Samples of breast milk, vaginal swabs and infant faeces were aseptically collected from five mothers whose neonates were born by vaginal delivery and another five that had their babies by caesarean section. After polymerase chain reaction (PCR) amplification using Lactobacillus group-specific primers, amplicons were analysed by denaturing gradient gel electrophoresis (DGGE). Clone libraries were constructed to describe the Lactobacillus group diversity. DGGE fingerprints were not related to the delivery method. None of the species detected in vaginal samples were found in breast milk-derived libraries and only few were detected in infant faeces. The bacterial composition of breast milk and infant faeces is not related to the delivery method. It has been suggested that neonates acquire lactobacilli by oral contamination with vaginal strains during delivery; subsequently, newborns would transmit such bacteria to the breast during breastfeeding. However, our findings confirm, at the molecular level that in contrast to the maternal vagina, breast milk seems to constitute a good source of lactobacilli to the infant gut.

Analysis of genital Candida albicans infection by rapid microsatellite markers genotyping

Candida albicans (C. albicans) infection, often occurring in genital candidiasis, has increased dramatically recently. Developing an efficient C. albicans typing method may contribute to understanding its epidemiological characteristics and guiding efficient treatment. We used rapid microsatellite genotyping assay for interstrain differentiation of C. albicans isolates and explored some characteristics of its spread. DNA was extracted from C. albicans isolates from gentalia, recta and mouths of 39 female cases and 27 male cases of genital candidiasis. Three fluorescent primers for the microsatellite markers in conserved genes (CDC3, EF3 and HIS3) of C. albicans were used to amplify the isolates DNA by PCR. Fluorescent signals were read with an automatic sequencer and analyzed with GeneScan software. Analysis of the three microsatellites markers showed 18 gene allelic associations in genital C. albicans infected patients: 10 allelic associations in female and 11 allelic associations in male, of which 3 allelic associations shared by both genders covered 71% of infections. The most dominant allele association of pathogenic strains for both genders was 116:124, 122:131, 160:200 that covered about 50% of infection. Gentalia and recta shared the same strains in 80% of female patients, but in only 3.8% of male patients. There were 2.7% female patients, but no males, with same strain in both gentalia and mouths. Five of seven genital C. albicans infected couples had the same allelic associations of which 4 were the dominant pathogenic C. albicans susceptible for both genders. The predominant allelic association of the pathogenic strain in genital C. albicans infection is 116:124, 122:131, 160:200. Vaginal pathogenic strains are probably maintained from the rectal reservoir. Pathogenic strains of male patients are probably from frequent sexual intercourse. The aggressiveness of some strains varies with gender.

Deletion ofALS5,ALS6orALS7increases adhesion ofCandida albicansto human vascular endothelial and buccal epithelial cells

Candida albicans yeast forms deleted for ALS5, ALS6 or ALS7 are more adherent than a relevant control strain to human vascular endothelial cell monolayers and buccal epithelial cells. In the buccal and vaginal reconstituted human epithelium (RHE) disease models, however, mutant and control strains caused a similar degree of tissue destruction. Deletion of ALS5 or ALS6 significantly slowed growth of the mutant strain; this phenotype was not affected by addition of excess uridine to the culture medium. These studies demonstrate similar phenotypic characteristics for the als5Delta/als5Delta, als6Delta/als6Delta and als7Delta/als7Delta strains that are not observed in any of the other C. albicans alsDelta/alsDelta isolates.

Protective Effect of VaginalLactobacillus paracaseiCRL 1289 against Urogenital Infection Produced byStaphylococcus aureusin a Mouse Animal Model

Urogenital infections of bacterial origin have a high incidence among the world female population at reproductive age. Lactobacilli, the predominant microorganisms of the healthy vaginal microbiota, have shown a protective effect against the colonization and overgrowth of urogenital pathogens that increased the interest for including them into probiotics products assigned to restore the urogenital balance. In the present work, we determined in a mouse animal model the capability of Lactobacillus paracasei CRL 1289, a human vaginal strain with probiotic properties, to prevent the vaginal colonization of a uropathogenic strain of Staphylococcus aureus. Six-week-old female BALB/c mice, synchronized in their estral cycle, were intravaginally inoculated with two doses of 109 lactobacilli before challenging them with a single dose of 105 or 107 CFU of S. aureus. The vaginal colonization of both microorganisms and the effect on the vaginal structure were determined at 2, 5, and 7 days after pathogen inoculation. Control mice and those challenged only with the pathogen showed an insignificant lactobacilli population, whereas 105 lactobacilli/mL of vaginal homogenate were recovered at 2 days after challenge from the L. paracasei CRL 1289 and the probiotic + pathogen groups, decreasing this number on the following days. The treatment with L. paracasei CRL 1289 decreased significantly the number of staphylococci recovered at 2 and 5 days when mice were challenged only with 105 CFU of pathogen. The inoculation of S. aureus produced a remarkable inflammatory response and structural alterations in the vaginal mucosa that decreases in a significant manner when the mice were protected with L. paracasei CRL 1289. The results obtained suggest that this particular Lactobacillus strain could prevent the onset of urogenital infections by interfering with the epithelial colonization by uropathogenic S. aureus.

Purification and characterization of enterocin 62-6, a two-peptide bacteriocin produced by a vaginal strain ofEnterococcus faecium: Potential significance in bacterial vaginosis

A bacteriocin produced by a vaginal isolate of Enterococcus faecium strain 62-6, designated enterocin 62-6, was characterized following purification and DNA sequence analysis and compared to previously described bacteriocins. Enterocin 62-6 was isolated from brain heart infusion (BHI) culture supernatants using ammonium sulfate precipitation followed by elution from a Sepharose cation exchange column using a continuous salt gradient (0.1-0.7 M NaCl). SDS-PAGE of an active column fraction resulted in an electrophoretically pure protein, which corresponded to the growth inhibition of the sensitive Lactobacillus indicator strain in the gel overlay assay. Purified enterocin 62-6 was shown to be heat- and pH-stable, and sensitive to the proteolytic enzymes alpha-chymotrypsin and pepsin. Results from mass spectrometry suggested that it comprised two peptides of 5206 and 5219+/-1 Da, which was confirmed by DNA sequence analysis. The characteristics of enterocin 62-6 as a small, heat- and pH-stable, cationic, hydrophobic, two-peptide, plasmid-borne bacteriocin, with an inhibitory spectrum against a broad range of Gram-positive but not Gram-negative bacteria, were consistent with its classification as a class IIc bacteriocin. Furthermore, its wide spectrum of growth inhibitory activity against Gram-positive bacteria of vaginal origin including lactobacilli, and stability under the acidic conditions of the vagina, are consistent with our hypothesis that it could have potential significance in disrupting the ecology of the vaginal tract and pave the way for the establishment of the abnormal microbiota associated with the vaginal syndrome bacterial vaginosis. This is the first class IIc bacteriocin produced by a strain of E. faecium of vaginal origin to be characterized.

Prevention and treatment of urogenital infections and complications: lactobacilli's multi-pronged effects

The association between depletion of vaginal lactobacilli and increased risk of various urogenital infections and complications such as preterm labor, has been known for some time. Restoration of depleted lactobacilli by administration of probiotic strains has been demonstrated in humans using Lactobacillus rhamnosus GR-1 and L. reuter i RC-14. These organisms also augment antibiotic efficacy, lessen the side effects of these drugs, and alleviate diarrhea in AIDS patients. The mechanisms appear to be multi-factorial, and include production of: (i) anti-microbial factors such as lactic acid, bacteriocins, hydrogen peroxide, (ii) biosurfactants or other components that affect pathogen colonization and biofilm formation, (iii) signalling compounds that influence pathogen virulence expression, and (iv) signalling compounds that modulate immunity. Recombinant strains have been produced that inhibit or kill HIV, offering hope for microbicide applications that can be self-used by women. As more information becomes available about the ‘normal’ versus ‘disease prone’ vaginal microbiota and strains that confer the most benefits, current and new probiotic remedies will potentially provide improved restorative and therapeutic options to lower the one billion urogenital infections currently afflicting women around the world. Key words: probiotics, lactobacillus, urogenital infections, mechanisms

Engineered VaginalLactobacillusStrain for Mucosal Delivery of the Human Immunodeficiency Virus Inhibitor Cyanovirin-N

Women are at significant risk of human immunodeficiency virus (HIV) infection, with the cervicovaginal mucosa serving as a major portal for virus entry. Female-initiated preventatives, including topical microbicides, are urgently needed to help curtail the HIV/AIDS pandemic. Here we report on the development of a novel, live microbicide that employs a natural vaginal strain of Lactobacillus jensenii engineered to deliver the potent HIV inhibitor cyanovirin-N (CV-N). To facilitate efficient expression of CV-N by this bacterium, the L. jensenii 1153 genome was sequenced, allowing identification of native regulatory elements and sites for the chromosomal integration of heterologous genes. A CV-N expression cassette was optimized and shown to produce high levels of structurally intact CV-N when expressed in L. jensenii. Lactobacillus-derived CV-N was capable of inhibiting CCR5-tropic HIV(BaL) infectivity in vitro with a 50% inhibitory concentration of 0.3 nM. The CV-N expression cassette was stably integrated as a single copy into the bacterial chromosome and resolved from extraneous plasmid DNA without adversely affecting the bacterial phenotype. This bacterial strain was capable of colonizing the vagina and producing full-length CV-N when administered intravaginally to mice during estrus phase. The CV-N-producing Lactobacillus was genetically stable when propagated in vitro and in vivo. This work represents a major step towards the development of an inexpensive yet durable protein-based microbicide to block the heterosexual transmission of HIV in women.

Species diversity and relative abundance of vaginal lactic acid bacteria from women in Uganda and Korea

Lactobacilli play an important role in maintaining vaginal health of women. The aim of this study was to compare the species richness and relative abundance of Lactobacillus and other lactic acid bacteria in women of two geographically distant countries, Uganda and Korea. Vaginal samples were obtained from two women populations in Uganda and Korea. The Lactobacillus Rogosa SL agar was used for initial isolation of lactic acid bacteria. After phenotypic analyses, the 16S rRNA gene was amplified by polymerase-chain reaction and analysed by the BLAST program and phylogenetic tree construction. A total of 338 (128 Korean and 210 Ugandan) vaginal lactic acid bacterial strains were isolated, including five genera: Lactobacillus, Leuconostoc, Pediococcus, Streptococcus and Weissella. While Lactobacillus crispatus was common in both populations, Lactobacillus fermentum was common only in Korean women, and Lactobacillus gasseri, Lactobacillus reuteri and Lactobacillus vaginalis only in Ugandan women. Among other lactic acid bacteria, Weissella was more common in Ugandan, and Pediococcus in Korean women. All Weissella strains produced hydrogen peroxide, and all Pediococcus strains inhibited Candida species. Although many lactic acid bacteria colonize women, their species distributions may be different in women of geographically separated communities. The knowledge of species richness and relative abundance of vaginal lactic acid bacteria, including Lactobacillus, Pediococcus and Weissella, may lead to the design of better probiotic products as bacterial replacement therapy.