Protein and Carbohydrate Composition of Cecal Contents of Gnotobiotic Rats and Mice ∗

Abstract

Summary

Cecal contents of gnotobiotic rats and mice have 10 times as much soluble protein and from 20 to 200 times as much soluble carbohydrate as their conventional controls. About 12-29% of the soluble protein was precipitated by 10% TCA and was shown to contain elevated levels of trypsin and chymotrypsin (i.e., from 90 to 200 more than conventional animals per 100 gm of body wt.). Another 30-50% of the protein was soluble in 10% TCA but could be precipitated by 80% ethanol. The material was most likely mucinous in nature as it contained carbohydrate and was of high molecular weight. The gnotobiotic ceca had 5-8 times more insoluble material per 100 gm of body weight than that found in conventional ceca. The demonstration of endogenous enzymes and high molecular weight mucins suggested that there is an impairment in the digestion and reabsorption of endogenous nitrogen in the gnotobiotic animals.