ABSTRACT
AIMS: To assess glutathione (GSH) biosynthesis ability and activity of dependent enzymes in food-grade lactic acid bacteria (LAB) and correlating with genomic information on GSH system in LAB. METHODS AND RESULTS: Whole-genome sequences of 26 food-grade LAB were screened for the presence/absence of a set of genes involved in de novo GSH system. Multiple strains of Streptococcus thermophilus (37), Lactobacillus casei (37), Lactobacillus rhamnosus (4), Lactobacillus paracasei (8) Lactobacillus plantarum (23) and Lactobacillus fermentum (22) were screened for biochemical evidence of the GSH system. Multiple sequence analysis of GshF sequences was carried out for comparing the genomic signatures between GSH-producing and nonproducing species. CONCLUSIONS: Streptococcus thermophilus was found to have de novo GSH biosynthesis as well as import ability. Lactobacillus sp. were negative for GSH synthesis but could import it from the medium. All the species exhibited prolific GSH reductase and peroxidase activity. Sequence analysis revealed the absence of key amino acid residues as well as a truncated N-terminal region in lactobacilli. SIGNIFICANCE AND IMPACT OF THE STUDY: The study provides a comprehensive view on the status of an important antioxidative system (the GSH system) in LAB and is expected to serve as a primer for future work on the mechanistic role of GSH in the group.
ABSTRACT
The central nervous system of Carcinoscorpius rotundicauda contains two types of NSCs (A and B) differing as regards their size, cytoarchitecture and distribution. They are clearly distinguishable when stained with azan and Masson's trichrome, but react weakly to PAF and CHP. The A cells are large, with fine cytoplasm granules (NSM), and are distributed below the perineurium, while the B cells are much smaller, contain coarse granules and are distributed in the vicinity of the neuropil. The posterior third of the circumoesophageal ring and the abdominal ganglia contain a far larger number of NSCs compared to the anterior part of the CNS. The ability of NSC groups to form numerous axon bundles, decussation of the neurosecretory axons, the presence of a rich capillary network round neurosecretory perikaryons and the appearance of atypical neurons in the anteromedian part of the CNS are further striking features discussed with reference to the neurosecretory phylogeny of the species in question.
