Bacillus Pasteurii: A Small Microbe with Huge Potential
Anthony Macherone, Natarajan Ranganathan, Beena Patel
¹Kibow Biotech, Inc. Philadelphia, PA, ²Down State Medical Center, BHSC-SUNY, Brooklyn, NY.
Journal of the American Society of Nephrology 13: Sept 2002 pp. 766A PUB474
Our efforts to find an intra-intestinal means for treating kidney failure has focused on the use of microbes to eliminate urea via the catabolic activity of urease. Two questions that have arisen are :
1.) What happens to the theoretically large amount of ammonia produced by the hydrolysis of urea?
2.) How much bacteria will a patient have to consume per day for the treatment to be efficacious?
Herein we present the information generated thus far.
B. pasteurii is a soil-borne microbe that is known to be non-toxigenic and non-pathogenic to the human species. Although it is not thought to be an indigenous inhabitant of the human intestine, it has been isolated from human feces and is considered a contaminate of the gut.
Forty milligrams of lyophilized B. pasteurii was placed in 100mL artificial intestinal fluid (AIF) fortified with 100mg/dL urea and incubated at 37 degrees C. An ammonia specific ion-selective electrode was used to monitor the production of ammonia. Aliquots of the solution were taken in twenty-minute intervals and evaluated for residual urea content. It was determined that the urea was completely hydrolyzed in one hour and less than 5mg/dL ammonia was produced. These results were compared to pure urease enzyme which hydrolyzed the urea in five minutes with the production of ~55mg/dL ammonia.
To evaluate a possible daily regimen, 40mg lyophilized B. pasteurii was placed in 100mL AIF fortified with 100mg/dL urea and incubated at 37 degrees C. After one hour, a sample was taken for urea determination and 100mg more urea added to the AIF solution. This sequence was repeated over eight hours for a total of 800mg added urea. It was determined that over the time frame of the experiment, that B. pasteurii hydrolyzed ~ 85% of the urea.
We have determined that B. pasteurii efficiently hydrolyzed urea and produced far less ammonia than pure urease. This result can be attributed to the uptake of ammonia by the bacteria as a source of nitrogen for growth. Also, B. pasteurii can hydrolyze urea in a ratio of about 1 part bacteria per 25 parts urea leading to a possible daily dosage of approximately one gram.