Monitoring Growth Compatibility and Bacteriocin Gene Transcription of Adjunct and Starter Lactic Acid Bacterial Strains in Milk.

ABSTRACT: When developing protective starter cultures for application in cheese technologies, monitoring growth interactions between starter and adjunct lactic acid bacterial (LAB) species and in situ expression of bacteriocin genes in the mixtures is crucial. This study first aimed to monitor the growth of mixed LAB strain populations during milk model fermentations by microbial counts and real-time quantitative PCR. The primary starter strains, Streptococcus thermophilus ST1 and costarter Lactococcus lactis subsp. cremoris M78, served as the basic starter composite coinoculated in all milk treatments. Adjunct bacteriocinogenic Enterococcus faecium strains KE82 and GL31 and the ripening Lactiplantibacillus plantarum H25 strain were added separately to the starter composite, resulting in four LAB combination treatments. The second aim was to quantify gene transcripts of nisin and enterocins B and A synthesized by strains M78, KE82, and GL31, respectively, by reverse transcription-real-time quantitative PCR and to detect the in situ antilisterial effects of the cocultures. Adjunct LAB strains showed growth compatibility with the starter, since all of them exhibited 2- to 3-log-unit increases in their population levels compared to their initial inoculation levels, with ST1 prevailing in all treatments. KE82 grew more competitively than GL31, whereas cocultures with KE82 displayed the strongest in situ antilisterial activity. Nisin gene expression levels were higher at the exponential phase of microbial growth in all treatments. Finally, the expression levels of nisin and enterocin A and B genes were interrelated, indicating an antagonistic activity.

Reverse Transcriptase Affects Gametogenesis and Preimplantation Development in Mouse.

BACKGROUND/AIM: The expression of reverse transcriptase (RT) in ovaries, testes, gametes and embryos highlights its critical role in cell growth and differentiation. We sought to investigate the effects of the potent RT inhibitor lamivudine in gametogenesis and mouse embryo preimplantation development. MATERIALS AND METHODS: Male and female FVB/N mice were treated with the reverse transcriptase inhibitor Lamivudine for seven consecutive weeks. Following treatment, mouse sperm parameters, testicular and ovarian morphology as well as post-IVF embryo development were evaluated. RESULTS: Lamivudine impaired the sperm parameters and the testicular structure in male mice, the number of primordial germ cells and primary oocytes in ovaries of female mice, and the embryos' morphology and development up to the blastocyst stage during in vitro culture. CONCLUSION: The administration of lamivudine affected the processes of spermatogenesis and oogenesis as well as the in vitro preimplantation development of mouse embryos.

UGT1A6- and UGT2B7-related valproic acid pharmacogenomics according to age groups and total drug concentration levels.

AIM: The role of UGT1A6 and UGT2B7 polymorphisms and the impact of total drug plasma concentration in valproic acid (VPA) pharmacogenomics. PATIENTS & METHODS: A total of 134 Greek patients were recruited (76 adults). Patients were genotyped for UGT1A6 19T>G, 541A>G and 552A>C and UGT2B7 802T>C polymorphisms. Patients' demographic and clinical data were registered. Natural logarithm of concentration-to-dose ratio (CDR) was also calculated as the final outcome. RESULTS: No significant genotype-related differences in VPA metabolism were noted among various subgroups. An increased lnCDR ratio was noted in children patients compared with adults suggesting increased metabolic capability in younger ages. CONCLUSION: UGT1A6 and UGT2B7 genotypes were not related to significant changes in VPA metabolism, even after controlling for total drug concentration levels. Younger ages were associated with increased VPA clearance rate.