Genetic Detection of the ALS1 Virulence Gene in Clinical Candida albicans Isolates from Human Gut Samples in Erbil Governorate, Kurdistan Region, Iraq: Genetic Detection of the ALS1 Virulence Gene in Clinical Candida albicans Isolates

Hewa A. Mohammed; Taha J. Omar Zrary

doi:10.63841/iue31652

Authors

Hewa A. Mohammed Department of Medical Microbiology, Faculty of Science and Health, Koya University, Koya 44023, Kurdistan Region– F.R. IRAQ Author https://orcid.org/0009-0009-2376-7494
Taha J. Omar Zrary Department of Medical Microbiology, Faculty of Science and Health, Koya University, Koya 44023, Kurdistan Region– F.R. IRAQ Author https://orcid.org/0000-0001-8646-097X

DOI:

https://doi.org/10.63841/iue31652

Keywords:

Candida albicans, Gastrointestinal Candidiasis, ALS1 virulence gene, PCR, Sequencing

Abstract

Candida albicans is a common commensal of the human gastrointestinal tract (GIT) but can become an opportunistic pathogen under immunocompromised conditions. The ALS1 gene, part of the agglutinin-like sequence (ALS) family, encodes an adhesin that facilitates tissue attachment and biofilm formation, contributing significantly to C. albicans pathogenicity. This study aimed to determine the prevalence of C. albicans in clinical GIT samples and assess the presence of the ALS1 virulence gene among these isolates, using classical and molecular techniques.

A total of 121 stool samples were collected from patients with GIT symptoms in Koya and Erbil City. Culturing was performed on Sabouraud Dextrose Agar and HiCrome™ for preliminary identification, followed by Gram staining, germ tube testing, and confirmation with the VITEK 2 ID system. Molecular detection of the 18S rRNA and ALS1 genes was conducted via colony PCR, and selected amplicons were verified by Sanger sequencing and BLAST alignment.

Candida. albicans was isolated in 22.3% (27/121) of samples. Of these, 81.5% (22/27) tested positive for the ALS1 gene. PCR products were confirmed by sequencing, revealing high identity with reference strains in GenBank. Combining phenotypic and molecular assays ensured robust and accurate identification.

The high prevalence of ALS1 among GIT-derived C. albicans isolates highlights its potential as a molecular marker for virulence and colonization risk.

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Author Biographies

Hewa A. Mohammed, Department of Medical Microbiology, Faculty of Science and Health, Koya University, Koya 44023, Kurdistan Region– F.R. IRAQ

Hewa A. Mohammed got the B.Sc. degree in Medical Microbiology at Department of Medical Microbiology, Faculty of Science and Health, Koya University. currently working as a laboratory assistant at Koya University and studying M.Sc in the same field. His research interests are in, Microbiology, Molecular Microbiology, and Anti-Fungal agents
Taha J. Omar Zrary, Department of Medical Microbiology, Faculty of Science and Health, Koya University, Koya 44023, Kurdistan Region– F.R. IRAQ

Welcome to my Academic Profile page. My name is Taha Jalal Omar. I am an Assistant Professor teaching in the Department of Medical Microbiology, Faculty of Science and Health at Koya University, Kurdistan Region, F.R. Iraq.

I have a B.Sc. degree in Biology, M.Sc. degree in Biology and a Ph.D. degree in Mycology. I am a member of Kurdistan Biological Syndicate. I am an member Editor board of Journal of Fungi and other scientific Journals.

My research interest includes Mycology, Mycotoxin and Fugal physiology.

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Genetic Detection of the ALS1 Virulence Gene in Clinical Candida albicans Isolates from Human Gut Samples in Erbil Governorate, Kurdistan Region, Iraq