Molecular characterization and phylogenetic analysis of babA gene of Helicobacter pylori isolated from Indian patients with gastrointestinal diseases

Sarika Singh; Amresh Kumar Sharma; Anup Som; Valentina Gehlot; Shweta Mahant; Prateek Sharma; Kunal Das; Rajashree Das

doi:10.1016/j.gene.2024.148526

Molecular characterization and phylogenetic analysis of babA gene of Helicobacter pylori isolated from Indian patients with gastrointestinal diseases

Gene. 2024 May 3:920:148526. doi: 10.1016/j.gene.2024.148526. Online ahead of print.

Authors

Sarika Singh¹, Amresh Kumar Sharma², Anup Som³, Valentina Gehlot⁴, Shweta Mahant⁵, Prateek Sharma⁶, Kunal Das⁷, Rajashree Das⁸

Affiliations

¹ Centre for Medical Biotechnology, Amity Institute of Biotechnology, Amity University, Noida 201301, UP, India. Electronic address: sarikasingh.chd@gmail.com.
² Centre of Bioinformatics, Institute of Interdisciplinary Studies, University of Allahabad, Prayagraj 211002, UP, India. Electronic address: amresharma1@gmail.com.
³ Centre of Bioinformatics, Institute of Interdisciplinary Studies, University of Allahabad, Prayagraj 211002, UP, India. Electronic address: som.anup@gmail.com.
⁴ Centre for Medical Biotechnology, Amity Institute of Biotechnology, Amity University, Noida 201301, UP, India. Electronic address: valentinasain@gmail.com.
⁵ Centre for Medical Biotechnology, Amity Institute of Biotechnology, Amity University, Noida 201301, UP, India. Electronic address: shwetabanerjeemahant@gmail.com.
⁶ Centre for Medical Biotechnology, Amity Institute of Biotechnology, Amity University, Noida 201301, UP, India. Electronic address: shubhsharma009@gmail.com.
⁷ Department of Gastroenterology, Yashoda super specialty Hospital, Ghaziabad, 201001, U.P, India. Electronic address: drkunaldas@yahoo.com.
⁸ Centre for Medical Biotechnology, Amity Institute of Biotechnology, Amity University, Noida 201301, UP, India. Electronic address: rdas@amity.edu.

PMID: 38703866
DOI: 10.1016/j.gene.2024.148526

Abstract

Introduction: Outer membrane protein (OMP) of Helicobacter pylori (H. pylori) i.e., blood group antigen binding adhesin (babA) is responsible for the attachment of H. pylori in the gastric epithelium. Its adherence is causative for gastric pathology such as gastritis, peptic ulcer disease (PUD), or digestive tract disorders like erosive reflux disease (ERD) and (NERD) non-erosive reflux disease and together called Gastroesophageal reflux disease (GERD). BabA manifests rapid and varied selection via substitution of amino acid in its Leb-carbohydrate binding domain (CBD) which enables better binding preferences for distinct human populations and ABO blood group phenotypes. The positive evolutionary selection of the pathogenic factor of this genetically diverse bacterium has enabled it to adapt to the host gastric environment. Analyzing the association of virulent genes (cagA, vacA) and babA will help us better understand bacteria's pathogenicity.

Method: 109 H. pylori strains from patients with distinct gastrointestinal diseases were genotyped using Polymerase Chain Reaction(PCR) for cagA, vacA, and babA followed by Sanger sequencing and phylogenetic analysis.

Result: In the babA + ve genotype, a statistically significant association with p = 0.04 and < 0.0001 is seen in gastritis and ERD respectively. A significant association of genotype vacAs1m2 (p = 0.0002) was seen in gastritis, vacAs1m1 (p = 0.02) in NERD, vacAs1m1 (p < 0.0001) and vacAs1m2 (p = 0.002) in ERD. This relationship helps to detect gastritis or ERD where BabA gene can be used as an independent marker for detecting their presence.

Conclusion: The appearance of variants within distinct disease categories is due to local genetic variation.

Keywords: Gastroesophageal reflux disease (GERD); Helicobacter pylori; Molecular characterization; Peptic ulcer disease (PUD); Phylogenetic analysis; babA gene.