Comparative analysis of the Hom family of outer membrane proteins in isolates from two geographically distinct regions: The United States and South Korea

Abstract

En masse, our data show that the homA, homB, and homC profiles vary based upon the geographic origin of the strain; however, the fourth member of the hom family, homD, is more highly conserved. Additionally, protein topology modeling showed that many of the less well-conserved regions between homA and homB and between homC and homC corresponded to predicted environmentally exposed loops, suggesting that the divergence of the Hom family may be due to host adaptation/pressure.

ArsRS-Dependent Regulation of homB Contributes to Helicobacter pylori Biofilm Formation

“…HomB can be found at two different chromosomal loci (Oleastro et al, 2009a ; Servetas et al, 2018 ). To assess homB promoter variability based on the chromosomal locus, we first used BLAST to determine the overall conservation between the homB promoter regions available in Genbank.…”

“…Furthermore, mutation of a single domain in AlpB, which is predicted to be in an environmentally exposed loop, effected biofilm development by TK1402 (Yonezawa et al, 2017 ). Notably, differences between the HomB and HomA paralogs are also predicted to reside in environmentally exposed loops (Servetas et al, 2018 ). Thus, these findings present an interesting avenue to pursue in the identification of functional difference between HomA and HomB.…”

“…Additionally, two interesting observations that arose from the epidemiological studies were that (1) homB could occupy two different loci, locus A and locus B, and (2) strains can carry a single or double copy of homB (Oleastro et al, 2009a , 2010 ; Kang et al, 2012 ). To date, neither phase variation nor recombination has been demonstrated for homB ; however, differences in distribution of homB location and copy number have been reported (Oleastro et al, 2009a ; Servetas et al, 2018 ). This is particularly intriguing given that the homB genotype varies between Western and East Asian isolates and because the association between homB and disease severity is dependent on the population being studied (Oleastro et al, 2008 , 2009b ; Jung et al, 2009 ; Hussein, 2011 ; Talebi Bezmin Abadi et al, 2011 ; Kang et al, 2012 ).…”

Correlation between the geographical origin of Helicobacter pylori homB-positive strains and their clinical outcomes: a systematic review and meta-analysis

“…The hom genes are known as a small paralogous family of adhesion proteins and are distinguished from other OMPs by the signal sequence and hydrophobic motif located in the Cterminal domain (13). The hom family consists of four classes homA, homB, homC, and homD, so that homA and homB are encoded by one locus, while each of homC and homD is encoded by a distinct locus (13,14). Despite 90% similarity between homA and homB, studies show that the distribution of each is speci c in each geographic area, so that homA is a diagnostic marker for East Asian strains, and homB has global distribution (14,15).…”

“…The hom family consists of four classes homA, homB, homC, and homD, so that homA and homB are encoded by one locus, while each of homC and homD is encoded by a distinct locus (13,14). Despite 90% similarity between homA and homB, studies show that the distribution of each is speci c in each geographic area, so that homA is a diagnostic marker for East Asian strains, and homB has global distribution (14,15). Recently, the relationship between homB and severe clinical outcomes has attracted much attention; the product of homB, HomB is a virulence factor that contributes to several bacterial activities such as bio lm formation, antibiotic resistance, delivery of CagA from type 4 secretion system (T4SS), induction of IL-8 production, gastritis, corpus atrophy, and persistent colonization (16)(17)(18).…”