Rate of Urea Hydrolysis

Nitrogenous solutes accumulate in the blood of uremic patients and flow into the bowel by simple passive diffusion. Our aim is to develop a non-invasive method of removing various uremic solutes from the bowel thus allowing the concentration gradient to continue functioning to lower overall serum levels of such solutes. We have evaluated numerous microbes for their ability to utilize various uremic solutes including, urea, uric acid, creatinine and host of other potentially harmful biochemicals. By designing and formulating a regimen of probiotics targeting these substances in the bowel, we seek to improve the patients overall health.

We have previously reported the urea utilizing abilities of soil borne microbe Bacillus pasteurii and genetically engineered urealytic E. coli and now compare these with GRAS status Streptococcus thermophilus KB19. (Urea utilization being the trait of interest for these microbes.) .

Escherichia colia
A Genetically engineered containing urease operon from Klebsiella aerogenes on multicopy plasmid – {source: Robert P. Hausinger, Michigan State University}
Not a constituent of normal gut flora
Not GRAS status

Bacillus pasteurii
Source: ATCC 6453
Soil microbe – non-pathogenic, non-toxigenic
High urease production
Isolated from human intestinal microflora
considered a contaminant, not indigenous to human gut
Not GRAS status

Both genetically engineered E. coli DH5 and soil borne bacterium B. pasteurii exhibit a high rate of urea hydrolysis but neither are Generally Recognized As Safe (GRAS) by the US FDA. Therefore, they are not presently suitable for human consumption. Kibow Biotech’s proprietary Streptococcus thermophilus KB19 is obtained and grown under proprietary conditions from a GRAS status yogurt culture. Based upon these findings reported here and the GRAS status, Streptococcus thermophilus KB19 appears to be a good candidate for inclusion in a nutraceutical product formulation. Kibow Biotech Inc. is evaluating other potential microbes for its oral microbial formulation towards uremia therapy.