In:
Antimicrobial Agents and Chemotherapy, American Society for Microbiology, Vol. 63, No. 9 ( 2019-09)
Abstract:
Salmonella genomic island 3 (SGI3) was first described as a chromosomal island in Salmonella 4,[5],12:i:–, a monophasic variant of Salmonella enterica subsp. enterica serovar Typhimurium. The SGI3 DNA sequence detected from Salmonella 4,[5],12:i:– isolated in Japan was identical to that of a previously reported one across entire length of 81 kb. SGI3 consists of 86 open reading frames, including a copper homeostasis and silver resistance island (CHASRI) and an arsenic tolerance operon, in addition to genes related to conjugative transfer and DNA replication or partitioning, suggesting that the island is a mobile genetic element. We successfully selected transconjugants that acquired SGI3 after filter-mating experiments using the S. enterica serovars Typhimurium, Heidelberg, Hadar, Newport, Cerro, and Thompson as recipients. Southern blot analysis using I-CeuI-digested genomic DNA demonstrated that SGI3 was integrated into a chromosomal fragment of the transconjugants. PCR and sequencing analysis demonstrated that SGI3 was inserted into the 3′ end of the tRNA genes pheV or pheR . The length of the target site was 52 or 55 bp, and a 55-bp attI sequence indicating generation of the circular form of SGI3 was also detected. The transconjugants had a higher MIC against CuSO 4 compared to the recipient strains under anaerobic conditions. Tolerance was defined by the cus gene cluster in the CHASRI. The transconjugants also had distinctly higher MICs against Na 2 HAsO 4 compared to recipient strains under aerobic conditions. These findings clearly demonstrate that SGI3 is an integrative and conjugative element and contributes to the copper and arsenic tolerance of S. enterica .
Type of Medium:
Online Resource
ISSN:
0066-4804
,
1098-6596
DOI:
10.1128/AAC.00429-19
Language:
English
Publisher:
American Society for Microbiology
Publication Date:
2019
detail.hit.zdb_id:
1496156-8
SSG:
12
SSG:
15,3
