Departamento de Producción Animal y Ciencia de los Alimentos, Facultad de Veterinaria, Miguel Servet 177, Zaragoza 50013, Spain.
Published: November 2005
AI Article Synopsis
Article Abstract
To study the absorption of microbial lysine in growing rabbits, a labelled diet (supplemented with (15)NH4Cl) was administered to six animals (group ISOT); a control group (CTRL, four rabbits) received a similar, but unlabelled, diet. Diets were administered for 30 d. An additional group of six animals were fed the unlabelled diet for 20 d and then the labelled diet for 10 d while wearing a neck collar to avoid caecotrophy (group COLL), in order to discriminate it from direct intestinal absorption. At day 30 animals were slaughtered and caecal bacteria and liver samples taken. The (15)N enrichment in amino acids of caecal bacteria and liver were determined by GC-combustion/isotope ratio MS. Lysine showed a higher enrichment in caecal microflora (0.925 atom% excess, APE) than liver (0.215 APE) in group ISOT animals, confirming the double origin of body lysine: microbial and dietary. The COLL group showed a much lower enrichment in tissue lysine (0.007 (se 0.0029) APE for liver). Any enrichment in the latter animals was due to direct absorption of microbial lysine along the digestive tract, since recycling of microbial protein (caecotrophy) was avoided. In such conditions liver enrichment was low, indicating a small direct intestinal absorption. From the ratio of [(15)N]lysine enrichment between liver and bacteria the contribution of microbes to body lysine was estimated at 23 %, with 97 % of this arising through caecotrophy. Absorption of microbial lysine through caecotrophy was 119 (se 4.0) mg/d, compared with 406 (se 1.8) mg/d available from the diet. This study confirms the importance of caecotrophy in rabbit nutrition (15 % of total protein intake).
Histatin 5 (Hst5) is a 24-amino-acid peptide naturally present in human saliva that has been proposed as a potential antifungal therapeutic. However, Hst5 is susceptible to degradation by secreted aspartyl proteases (Saps) produced by Candida albicans, which could limit its efficacy as a therapeutic. To better understand the role of the lysine residues of Hst5 in proteolysis by C.
Unlabelled: Two-component systems (TCS) enable bacteria to sense and respond to environmental signals, facilitating rapid adaptation. , a key oral pathobiont, employs the CarSR TCS to modulate coaggregation with various Gram-positive partners by regulating the expression of , encoding a surface adhesion protein, as revealed by RNA-Seq analysis. However, the direct regulation of the -containing operon ( ) by the response regulator CarR, the broader CarR regulon, and the signals sensed by this system remain unclear.
Background/objectives: After birth, mothers provide the best nutrition for the healthy growth and development of their infants and the developing gut microbiota through breastfeeding. When breastfeeding is not or insufficiently available, infant formula is the only safe alternative. The production of infant formula includes heat-processing, which may induce protein glycation.
Beef is a dominant meat commodity produced mainly from beef cattle breeds. Dairy cattle breeds are reared for milk production, but their calves could be raised to produce high quality meat subject to designated feeding. The objective here was to investigate the role of oregano oil-enriched diets on the quality characteristics of meat produced by Holstein bulls.
Department of Ecology and Environmental Studies, Florida Gulf Coast University, Fort Myers, FL, 33965, USA; School of Geosciences, University of South Florida, Tampa, FL, 33620, USA. Electronic address:
Harmful cyanobacterial blooms have been increasing globally, introducing new challenges for protecting aquatic ecosystems and human health. A combined algaecide treatment, similar to combination antibiotic therapy, may more rapidly and effectively remove cyanobacteria by broad targeting of different growth mechanisms, reducing the recovery of bloom-forming cyanobacteria. To confirm this hypothesis, hydrogen peroxide (10.
