Supplementary MaterialsAdditional document 1. from plants, animals and microorganisms are known to possess sperm immobilizing and spermicidal properties. Following this, in the quest for alternative means, we have cloned, over expressed and purified the recombinant sperm agglutinating factor (SAF) from isolated from the cervix of a woman with unexplained infertility. Methods Genomic library of was generated in using pSMART vector and screened for sperm agglutinating factor (SAF). The LY404187 insert in sperm agglutinating transformant was sequenced and was found to express ribonucleotide-diphosphate reductase- sub unit. The ORF was sub-cloned in pET28a vector, expressed and purified. The effect of rSAF on motility, viability, morphology, Mg++-dependent ATPase activity and acrosome status of human sperms was analyzed in vitro and contraceptive efficacy was evaluated in vivo in female BALB/c mice. Results The 80?kDa rSAF showed complete sperm agglutinationinhibited its Mg2+-ATPase activity, caused premature sperm acrosomal loss in vitro and mimicked the pattern in vivo showing 100% contraception in BALB/c mice resulting in prevention of pregnancy. The FITC labeled LY404187 SAF was found to bind the entire surface of spermatozoa. Vaginal application and oral administration of rSAF to mice for 14 successive days did not demonstrate any significant change in vaginal cell morphology, organ weight and tissue histology of reproductive and non-reproductive organs and had no negative impact in the dermal and penile irritation tests. Conclusion The Sperm Agglutinating Factor from natural microflora of human cervix, showed extensive potential to be employed as a safe vaginal contraceptive. [8]magainin-A from the skin of the African clawed frog [9, 10] nisin- a bacteriocin produced by [11C13] and subtilosin from and possess good spermicidal activity [14]. Recombinant proteins such as heat labile enterotoxin subunit B genetically linked with hCG- chain [15], recombinant bonnet monkey zona pellucida (ZP1) conjgated to diphtheria toxoid (used to immunize female baboons) [16] and sperm specific antigen, NZ1, have been reported to prevent pregnancy [17]. Also, various microorganisms reported to immobilize or agglutinate spermatozoa are [18], [19], [20], [21], [22] and [23]. Hence, bacterial proteins can be explored and developed as contraceptive agents. In this work, (isolated previously in our laboratory from the cervix of a woman with inexplicable infertility, was found to agglutinate human and mouse spermatozoa in vitroFurther, sperm agglutinating factor (SAF) was isolated and purified and was able to show complete sperm agglutination in vitro. However, as the gene responsible for sperm agglutinating activity was unknown and the production of SAF from wild type bacteria was very low, the present study was designed to identify the SAF and enhance its production by heterologous over expression and to further evaluate the efficacy of recombinant SAF as a contraceptive agent in a female mouse model. Methods Bacterial strains and plasmid isolated from the cervix of a woman with inexplicable infertility, showed sperm agglutinating activity and was identified by Matrix-assisted laser desorption/ionization (MALDI) Microflex LT mass spectrometer [24]. It was maintained in Brain Heart Infusion broth. Plasmid pSMART, expression vector pET28a and (was grown in Luria Broth (LB) at 37?C/180?rpm for 72?h, following which it was centrifuged at 10,000 xg for 10?min at 4?C. The supernatant was passed through a 0.22?m Millipore filter to ensure that it was cell free. The bacterial cells so obtained were washed twice with sterile PBS. Equal volumes of semen sample (40??106 spermatozoa ml??1), LY404187 whole cell culture or washed cells (107 cells ml??1) or cell free supernatant were mixed and incubated at 37?C for 0, FZD4 15, 30, 60, 120 and 240?min and observed for agglutination at 400X magnification under light microscope. Sterile LB was used as control. Construction of genomic library Chromosomal DNA was isolated and was restricted with HaeIII partially. The break down was operate on a LY404187 preparative gel LY404187 as well as the agarose gel including fragments (2C6?kb) was excised by sterile cutter to draw out DNA using the business QIAquick.