Phylogenetic Grouping of Dominant Fecal Escherichia coli Isolates from Healthy Males and Females in Al-Kut/Wasit Province/Iraq

Abstract

Fecal isolates of Escherichia coli are divided into four main phylogenetic groups designated A, B1, B2 and D. Most commensal strains belong to group A and have fewer virulence factors than the extra intestinal pathogenic E. coli strains (ExPEC). This study was mainly designed for phylogenetic grouping of commensal fecal E. coli isolates from healthy males and females in Al-Kut City/Wasit Province/Iraq using PCR-based protocols. Also ExPEC's virulence genes were detected among these isolates. Among this study included isolates (n=205), group A was the most common among both females' and males' isolates (68.5% vs. 63.0%, respectively), followed by groups: B1 (15.7% vs. 22.6%, respectively), D (10.7% vs. 9.5%, respectively), and B2 (4.1% vs. 4.7%, respectively). Gender distribution of phylogenetic groups showed insignificant differences between females and males. Females' and males' isolates did not differ significantly for all of the detected ExPEC's virulence genes, except for papC which was significantly (P ≤ 0.05) more prevalent among males' isolates (16.6%) than among females' isolates (6.6%). In both females' and males' isolates the most prevalent virulence genes were fimH (97.5% vs. 100%, respectively) and iucC (52.0% vs. 55.9%, respectively), whereas the least prevalent were sfa/foc (0% each) and hly (0.82% vs. 0%, respectively). Furthermore, virulence genes were concentrated in isolates clustered in group B2.In both females and males, high percent of dominant commensal fecal E. coli isolates from Iraqi people in Al-Kut City clustered in phylogroup A followed by groups B1 and D whereas group B2 was rare. Also, dominant fecal strains with ExPEC characteristics were much less prevalent.

Comparison of Commensal Escherichia coli Isolates from Adults and Young Children in Lubuskie Province, Poland: Virulence Potential, Phylogeny and Antimicrobial Resistance

“…The changes in the phylogenetic structure of the E. coli isolates from Europe during the period of 20 years may be the result of the increasing of food processing and change in dietary habits [ 1 , 25 ]. The results of the present study with the dominance of phylogroup B2 among E. coli isolates from adults are consistent with the previous reports presenting the second pattern of phylogenetic structure, whereas the predominance of isolates of phylogroup A among young children is in accordance with the first pattern [ 1 , 25 , 26 , 49 ]. The diet of young children aged 0.5–3 years is rather simple and in the most part consists of organic, less processed food as compared to adult diet.…”

“…E. coli assigned to phylogroup B2 dominated among adults, whereas phylogenetic group A isolates prevailed among young children. The distribution of the phylogroups among the human population represents two patterns, the first with predominance of group A typical for European population (in 1980s), Africa, South America and Asia [ 1 , 25 , 26 , 49 ], and the second pattern that the isolates of group B2 prevailed is characteristic for Europe in the 2000s, North America, Japan and Australia [ 1 , 25 ]. The changes in the phylogenetic structure of the E. coli isolates from Europe during the period of 20 years may be the result of the increasing of food processing and change in dietary habits [ 1 , 25 ].…”

“…Previous studies have reported the characteristics of commensal E. coli strains derived from adults [ 25 , 26 ], schoolgirls aged 7–16 [ 20 , 21 ] and from infants [ 15 , 24 , 27 ], whereas there is limited data in the literature regarding E. coli derived from young children aged 0.5–3. Moreover, it was also reported that the diversity and composition of microorganisms found in the intestine changes dramatically between birth and the age of 3 years [ 28 ].…”

Carbapenem resistance profiles of Pathogenic Escherichia coli in Uganda

“…In our study, phylogenetic analysis predominantly clustered E. coli clinical isolates into B2 followed by A, B1 and D and this corroborates with ndings from previous studies [67][68][69]. However, contradicting results have been reported worldwide where A is the most abundantly isolated phylogroup [70][71][72][73]. Distribution of E. coli phylogroups among different ecological zones is in uenced by environment factor; thus, this accounts for variability in prevalence of the phylogenetic groups in different countries [74].…”

“…This pattern of distributes indicates inter-region transmission of UPEC, DEC and commensals. It was observed that phylogenetic group A, B2 and D strains were majorly isolated from urine and this is in a rmative with all studies that conducted phylogenetic analysis of E. coli clinical isolates [67,[75][76][77] whereas B1 strains were predominantly isolated from anal/fecal swabs, this does not corroborate with previous studies which found phylogroup A strains as the most dominant fecal isolates [72,73,78].…”