16 research outputs found
Genome assisted probiotic characterization and application of Bacillus velezensis ZBG17 as an alternative to antibiotic growth promoters in broiler chickens
Not AvailableThe present study describes genome annotation and phenotypic characterization of Bacillus velezensis ZBG17 and
evaluation of its performance as antibiotic growth promoter substitute in broiler chickens. ZBG17 comprises 3.89
Mbp genome with GC content of 46.5%. ZBG17 could tolerate simulated gastrointestinal juices prevalent in the
animal gut. Some adhesion-associated genomic features of ZBG17 supported the experimentally determined cell
surface hydrophobicity and cell aggregation results. ZBG17 encoded multiple secondary metabolite gene clusters
correlating with its broad-spectrum antibacterial activity. Interestingly, ZBG17 completely inhibited Salmonella
enterica and Escherichia coli within 6 h and 8 h in liquid co-culture assay, respectively. ZBG17 genome analysis
did not reveal any genetic determinant associated with reported safety hazards for use as a poultry direct-fed
microbial. Dietary supplementation of ZBG17 significantly improved feed utilization efficiency and humoral
immune response in broiler chickens, suggesting its prospective application as a direct-fed microbial in broiler
chickens.Not AvailablePathogen exclusionantimicrobialsDirect fed microbial
Characterization of carbamoyl phosphate synthetase of <i>Streptomyces </i>spp.
931-935Carbamoyl phosphate synthetase (CPS)
activity in Streptomyces lividans was repressed (70%) by addition of
arginine and uracil in the growth medium. Enzyme activity was also inhibited by
UMP and activated by ornithine and IMP. Pattern of inhibition and activation
was similar irrespective of whether the cells were grown in medium supplemented
with arginine or with uracil. A mutant of S. coelicolor with dual
auxotrophy for arginine and uracil possessed only about 20% of CPS activity compared
to the wild-type strain. An activity staining protocol has been developed for
CPS enzyme. Using this method a single CPS band has been observed in the crude extracts
of Escherichia coli as well as in S. lividans. Taken together,
our results supported the conclusion that Streptomyces species might possess
a single CPS enzyme unlike other gram-positive bacteria, which show the presence
of two pathway-specific isozymes (Bacillus) or none (Lactobacillus
and Leuconostoc).</i