Research articles
ScienceAsia 52 (2026): 1-8 |doi:
10.2306/scienceasia1513-1874.2026.028
Genomic insights into arsenic and antibiotic resistance in
Comamonas thiooxydans strains F1-6 and A7-5
Kanchana Sitlaothaworna,*, Wongsakorn Phongsopitanunb, Kitja Chitpiromc, Engkarat Kingkaewd,
Jung-Sook Leee, Somboon Tanasupawatb,*
ABSTRACT: Two arsenic-resistant, Gram-negative, aerobic rod-shaped bacterial strains, F1-6 and A7-5, which were
isolated from agricultural soil in Thailand, were systematically studied. They grew at 30?C, pH 5?11, and in 3%
(w/v) NaCl. Ubiquinone with eight isoprene units (Q-8) and the cellular fatty acids C16:0, C18:1 ?7c, and C17:0 CYCLO
were the major components. Phylogenetic analysis via 16S rRNA gene sequences revealed that strains F1-6 and A7-5
were affiliated with the genus Comamonas and closely related to C. thiooxydans DF2T and C. testosteroni KCTC 2990T,
with 99.79% and 99.86% similarity, respectively. The average nucleotide identity and digital DNA-DNA hybridization
values between F1-6 and C. thiooxydans DF2T were 97.89% and 85.7%, respectively, whereas those between A7-5
and C. thiooxydans DF2T were 97.23% and 81.3%, respectively. Thus, both the F1-6 and A7-5 were identified as
C. thiooxydans. The draft genome sizes of F1-6 and A7-5 were 5.2 and 5.3 Mb, comprising 87 and 84 contigs, with
DNA G+C contents of 61.5% and 61.4%, respectively. The genomes of both strains contained ars cluster genes and
many genes for growth and resistance to heavy metals and antibiotics, similar to those of C. testosteroni ATCC 11996T,
C. thiooxydans CNB-1 substr. CNB-2 Chr, and C. terrae NBRC 106524T. Nevertheless, the acr3, qacG, and vanH genes
in the vanO cluster were found only in C. terrae NBRC 106524T. This study provides more comprehensive insight into
As-resistant bacteria and could be applied to the bioremediation of As and other heavy metals in the future.
Download PDF
Downloads Views
| a |
Department of Microbiology, Faculty of Science and Technology, Suan Sunandha Rajabhat University,
Bangkok 10300 Thailand |
| b |
Department of Biochemistry and Microbiology, Faculty of Pharmaceutical Sciences, Chulalongkorn University,
Bangkok 10330 Thailand |
| c |
Department of Occupational Health and Safety, Faculty of Science and Technology, Bansomdejchaopraya Rajabhat
University, Bangkok 10600 Thailand |
| d |
Department of Biology, School of Science, King Mongkut?s Institute of Technology Ladkrabang,
Bangkok 10520 Thailand |
| e |
Korean Collection for Type Cultures, Biological Resource Center, Korea Research Institute of Bioscience and
Biotechnology, Yuseong, Daejeon 305-806 Korea |
* Corresponding author, E-mail: Kanchana.si@ssru.ac.th, Somboon.T@chula.ac.th
Received 18 Nov 2024, Accepted 7 Mar 2026
|