title: Comparative evaluation of three supplements for Helicobacter pylori growth in liquid culture.
abstract: Helicobacter pylori, a microaerophilic fastidious bacterium, has been cultured on various plating and broth media since its discovery. Although the agar media can be sufficient for the identification, typing, and antibiotic resistance studies, no secretory antigen of H. pylori can be evaluated in such media. Thus, satisfactory growth of H. pylori in liquid culture which is needed for analysis of secretory proteins without the presence of interfering agents is in demand. We assessed the impact of beta-cyclodextrin, Fetal Bovine Serum (FBS), and charcoal as supplements for H. pylori growth. Furthermore, we aimed to identify the most favorable supplement that supports the secretion of the dominant secretory protein, vacuolating cytotoxin (VacA). Five clinical strains were cultured on broth media and the growth, viability, morphology, and protein content of each strain were determined. Our results revealed that beta-cyclodextrin supports the growth rate, viability, and cell lysate protein content to the extent similar to FBS. Application of beta-cyclodextrin is found to postpone spiral to coccoid conversion up to 72 h of incubation. Although FBS supports a higher VacA protein content, presence of interfering macromolecules in FBS questions its utility particularly for purposes of studying extra cellular proteins such as VacA. This study recommends further application of beta-cyclodextrin as a culture supplement with the potential capacity in neutralizing toxic compounds and flourishing the secretion of H. pylori proteins without addition of interfering proteins.
authors: Helicobacter Pylori Research Group, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran, 13164.
authors: Masoumeh
authors: M
authors: Douraghi
authors: Samaneh Saberi
authors: SS
authors: Kashani
authors: Hojjat
authors: H
authors: Zeraati
authors: Maryam
authors: M
authors: Esmaili
authors: Akbar
authors: A
authors: Oghalaie
authors: Marjan
authors: M
authors: Mohammadi
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism; D001431:Bacteriological Techniques; D003470:Culture Media / Q000737:chemistry*; D016480:Helicobacter pylori / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism*; D006801:Humans; D050296:Microbial Viability; D047392:beta-Cyclodextrins / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; C074689:VacA protein, Helicobacter pylori; D047392:beta-Cyclodextrins