BACKGROUND Pseudomonas aeruginosa might be converted to coccoid bacteria under antibiotic stress. Bacterial conversion would increase resistance to antibiotics due to changes in cell wall crosslink or decreased metabolic activity. Morphology of P. aeruginosa under stress conditions (presence of antibiotics) can be changed to elongated bacilli, U shape and finally coccoid bacteria. Results of se...

The nucleic acids of the helical and coccoid forms of Helicobacter pylori were studied to determine if the coccoid forms are "viable (capable of growing) but nonculturable." Using a reference strain (NCTC 11638) and five clinical strains, the nucleic acid contents, DNA integrity, and results of PCR and reverse transcription-PCR (RT-PCR) were compared for helical H. pylori and coccoid forms indu...

Helicobacter pylori is recognized as the most common pathogen to cause gastritis, peptic and duodenal ulcers, and gastric cancer. The organisms are found in two forms: (1) spiral-shaped bacillus and (2) coccoid. H. pylori coccoid form, generally found in the environment, is the transformed form of the normal spiral-shaped bacillus after exposed to water or adverse environmental conditions such ...

conclusions: despite the good in vitro bactericidal effect of amoxicillin on spiral forms of h. pylori, this antibiotic has little effect on induced coccoids that may develop after the inappropriate in vivo antibacterial treatment. hence, for successful therapy, it is essential not only to eradicate the spiral forms, but to eliminate the viable coccoids. background: helicobacter pylori (h. pylo...

conclusions results of the current study confirmed that molecular methods such as pcr and lamp were much more sensitive, rapid, and specific than culturing to identify non-culturable coccoid forms of h. pylori in water. results ten copies of targeted dna were required for pcr detection whereas only five copies gave a positive reaction by lamp assay, with 100% specificity. of the 10 isolates ino...

Helicobacter pylori was grown on solid medium for up to 5 weeks. Morphological conversion from spiral to coccoid forms began after 7 days incubation under microaerophilic conditions. Similar to the exponential cultures, the ageing bacteria produced alkaline phosphatase, acid phosphatase, leucine arylamidase and naphthol-AS-beta 1-phosphohydrolase, although there was a reduction in the levels of...