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Development of a recombinant ureolytic Lactococcus lactis for urea removal
Suai Zhang1, Dongxia Li, Kai Tian
1Key Laboratory of Bioactive Materials, Ministry of Education, College of Life Science, Nankai University, Tianjin, China.
Artificial Cells, Blood Substitutes, and Immobilization Biotechnology
|November 11, 2009
Summary
Genetically modified Lactococcus lactis efficiently removes urea, showing potential for treating kidney failure. Safety tests confirmed this food-grade bacteria is safe for consumption and effective in simulated gastrointestinal conditions.
Area of Science:
- Microbiology
- Biotechnology
- Nephrology
Background:
- Kidney failure is a prevalent condition requiring novel therapeutic strategies.
- Urea accumulation is a hallmark of renal failure, contributing to disease progression.
- Food-grade recombinant bacteria offer a promising avenue for urea removal therapies.
Purpose of the Study:
- To engineer a food-grade Lactococcus lactis strain expressing urease for urea removal.
- To evaluate the urea degradation efficiency of recombinant L. lactis under various conditions.
- To assess the safety and efficacy of the engineered strain in a simulated gastrointestinal environment.
Main Methods:
- Lactococcus lactis MG1363 was genetically modified with a urease gene.
- Urea removal activity was measured at different pH levels and nickel concentrations.
- The engineered strain's performance was tested in an artificial gastrointestinal model.
- Safety was assessed through feeding studies in rats, monitoring blood parameters and physiological indicators.
Main Results:
- Recombinant L. lactis demonstrated pH- and nickel-dependent urea removal, with optimal activity at pH 6.5 and 250 μM NiSO4.
- In simulated gastrointestinal conditions, urea removal reached approximately 65% within 24 hours.
- Safety trials showed no adverse effects on blood parameters, body weight, or food/water intake in rats.
Conclusions:
- Genetically modified Lactococcus lactis is a safe and feasible platform for urea removal.
- The engineered strain exhibits significant urease activity under simulated gastrointestinal conditions.
- This food-grade bacterium holds potential for developing novel treatments for chronic renal failure.
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