Helicobacter pylori Can Be Induced To Assume the Morphology of Helicobacter heilmannii

Abstract

Cultures of Helicobacter pylori obtained from the American Type Culture Collection (strain 43504) were grown as isolated colonies or lawns on blood agar plates and in broth culture with constant shaking. Examination of bacterial growth with Gram-stained fixed preparation and differential interference contrast microscopy on wet preparations revealed that bacteria grown on blood agar plates had a morphology consistent with that normally reported for H. pylori whereas bacteria from broth cultures had the morphologic appearance of Helicobacter heilmannii. Bacteria harvested from blood agar plates assumed an H. heilmannii-like morphology when transferred to broth cultures, and bacteria from broth cultures grew with morphology typical of H. pylori when grown on blood agar plates. Analysis by PCR of bacteria isolated from blood agar plates and broth cultures indicated that a single strain of bacteria (H. pylori) was responsible for both morphologies.

Helicobacter pylori free‐living and biofilm modes of growth: behavior in response to different culture media

“…In all three media with serum, as the culture aged, the spiral bacteria were replaced by U forms, coccoid bacteria and, predominantly, by very long bacteria, with a filamentous morphology; all these bacteria with different shapes presented a concomitant loss of viability, throughout time. The long spiral morphology was already reported by Fawcett et al (25), who referred that growth in liquid media with shaking can induce H. pylori to assume a long spiral morphology resembling that described for H. heilmanni. Therefore, culture conditions can be responsible for the change in morphology.…”

Persistent increase in myofibroblasts in Helicobacter heilmannii‐infected mice but not in Helicobacter pylori‐infected Mongolian gerbils: colocalization of COX‐2 and bFGF immunoreactivity

“…Further, H. pylori from broth cultures have been reported to show the morphological appearance of H. heilmannii. 8 In the present study, the localization of H. heilmannii was shown by toluidine blue staining and electron microscopy of Epon embedded-specimens, and crossreactivity with the monoclonal antibody against H. pylori. Development of more specific methods is therefore needed to clarify the actual significance of H. heilmannii in the gastric pathophysiology.…”

Detection of Non‐pylori Helicobacter Species in “Helicobacter heilmannii”‐Infected Humans

“…In these latter cases, it is unclear if the bacteria with HHLO morphology represented H. pylori rather than other Helicobacter species. It has been demonstrated that H. pylori can be induced to assume a "H. heilmannii"-like morphology [38]. Also, other yet unknown Helicobacter species could be involved in HHLO-induced disease and as such could have not been detected in this study.…”