Effects Of Bacterial Diet On Fat Distribution And Development In Caenorhabditis Elegans

It is known that the growth,development and reproduction of organisms are supported by matter and energy,which are obtained from external environment.Among these substances,there are macronutrients such as carbohydrates and proteins that mainly provide energy;there are also micronutrients(such as vitamins,cofactors and most minerals)that are essential for metabolic activities.The foods(animals and plants)ingested by mammals provide them with macronutrients and micronutrients needed for life.Microorganisms including the gut microbiota provide micronutrients to the host,or help the host absorb nutrients from food.Therefore,the microorganisms in the organism will affect the physiological and metabolic activities,as well as the health of host.It is difficult to systematically study the function and mechanism of microbial flora in mammals.Because mammals have a long lifespan and complex physiological structure.In recent years,C.elegans has been used as a suitable model to study the effects of diet on metabolism,physiology and gene expression.An important aspect of Microbes-C.elegans model is that bacteria act as food,which means that bacterial biomass is the main source of macronutrients,providing sufficient micronutrients for the nematode;bacteria can also act as the gut microbiota and have a synergistic relationship with the host,thus affecting the physical health of the host.In this study,we used C.elegans and its bacterial diet model to gain an in-depth understanding of the physiological effects of microbial flora.The standard laboratory diet for C.elegans is E.coli strain B OP50.Compared with the standard OP50 diet,different bacterial diets can cause major changes in the physiology and gene expression of C.elegans.This study found that feeding different E.coli could change the fat distribution of C.elegans.E.coli represented by HT115 caused the fat accumulation of the C.elegans RT130[pw Is23(vit-2::gfp)] on eggs,while E.coli represented by OP50 led to the fat distribution of nematode RT130[pw Is23(vit-2::gfp)] across the entire body.In a high-sugar environment,E.coli represented by OP50 can retard the development of C.elegans,while E.coli represented by HT115 has no effect on C.elegans development.By screening the E.coli Keio Knockout Collection bacterial bank,there were 3 E.coli gene mutants that could effectively alleviate the developmental effects of high glucose.One mutant gene is gln A,and we found that the addition of glutamic acid,a substrate of gln A,supported the development of C.elegans under high glucose condition.These studies will help us understand the effects of intestinal microorganisms on the development and health of the host(host's fat metabolism and obesity,etc.)...