Ethanol Plant Extracts and Essential Oils Susceptibility and Molecular Characterization of Facklamia hominis: An Emerging Atypical Gram-Positive Pathogen

This study aimed to detect the presence of atypical  Gram-positive bacteria and evaluate their susceptibility to selected plant extracts and essential oils through analysis of 200 diverse clinical specimens collected from patients in many hospitals in Mosul/ Iraq.

Specimens included blood, pus, vaginal swabs and urine, bacterial isolation and identification were performed using standardized microbiological techniques. Among the results, the species of the bacteria were very diverse, including Gram-positive and Gram-negative with particular distributions gained according to the source of a sample. Out of the isolates, 37 were Gram positive and they included general species of Staphylococcus spp.; Streptococcus spp.; Enterococcus spp.; and Lactobacillus Spp.

 Gram negative included Escherichia coli, Proteus spp.; Klebsiella spp. and Pseudmonas spp. as well as limited fungal isolates mainly Candida spp. Some of the samples showed absence of microbial growth. Of these four rare strains of the genus Facklamia spp.; namely Facklamia hominis, only four times occurring in two urines and two vaginal swab samples (Al-Saliem and Al-Rawy.;2005), and were confirmed by molecular investigation as species-specific PCR (16SrRNA gene sequencing). It was the first case of clinical strains of F. hominis to be reported in Iraq. These were deposited in GenBank (accession no. PV719694.1 to PV719697.1).

The comparative genomic results revealed considerable similarity to international strains, with local mutations, which might be the case of adaptation. Plant extracts and essential oils susceptibility testing provided different degrees of resistance which point to genetic diversity and plasticity of F. hominis.