Detection of urease and urease gene activities in Helibacter pylori with cell wall deficiency

ObjectiveTo probe the effect of cell wall deficiency on urease and urease gene activity in Heliobater pylori.MethodsThe stable L-form of Heliobater pylori(H pyloria)were induced by ceftriaxone sodium and isolated with filtration and then subcultured in non-high osmotic medium without antibiotic.H pyloria and its L-forms were identified by PCR of 16srDNA.The UreA gene and UreB gene was amplified with the specific PCR primer and the PCR products were detected with agarose gel electroforesis.ResultsL-form H pyloria could be induced by ceftriaxone sodium in non-high osmotic liquid medium.The shape of L-form H pyloria were spherical or elliptical.The single or paired L-form H pyloriac arranged in chain or in pile.The stable L-forms could pass through the filter with 0.22μm aperture and be subcultured in the non-high osmotic liquid medium without antibiotic or other inducer.The 16SrRNA gene fragment could be amplified from the stable L-form H pyloria.The stable L-form derived from H pyloria had UreA gene and UreB gene with the same nucleotide sequence as that of their parental bacteria.ConclusionThe cell wall deficient mutation would happen when the H pyloria is treated with ceftriaxone sodium,and the pure culture of stable L-form strains could be isolated with filtration and then subcultured in nonhigh osmotic medium without antibiotic.The stable L-form strains derived from H pyloria have UreA and UreB gene with the same nucleotide sequence as that of their parental bacteria.