Isolation and plasmid characterisation of Salmonella enterica serovar Albany harbouring mcr-5 from retail chicken meat in Japan

The emergence of plasmid-mediated colistin resistance genes (mcr), which is occurring in numerous countries, is a worldwide concern, primarily because colistin is a last-resort antibiotic. Compared to E. coli, prevalence of mcr genes in Salmonella is unclear in Japan. Here we screened for mcr-1-5 genes in our collection of Salmonella strains isolated from retail meat products collected in Japan from 2012 through 2016.
We found that Salmonella Albany strain 27A-368 encodes mcr-5 and that mcr genes were undetectable among the remaining 202 isolates.
The resistance plasmid p27A-368 was transferred by conjugation to S. Infantis and was stably retained as a transconjugant. Whole-genome sequencing revealed that mcr-5 resided on a 115 kb plasmid (p27A-368).
The plasmid backbone of p27A-368 is more similar to that of pCOV27, an ESBL-encoding plasmid recovered from avian pathogenic E. coli, rather than pSE13-SA01718 of S. Paratyphi B that encodes mcr-5.
Further, mcr-5 is located on a transposon, and its sequence is similar to that of pSE13-SA01718. A phylogenetic tree based on single nucleotide variants implies a relationship between 27A-368 and S. Albany isolated in Southeast Asian countries.

Isolation and characterization of two novel plasmids pCYM01 and pCYM02 of Cylindrospermum stagnale.

Cyanobacteria play a vital role in supplying nitrogen into the soil and aquatic ecosystem. It has an extra chromosomal DNA, whose role is not yet defined well.
Isolation and characterization of extra chromosomal DNA in cyanobacteria might help to understand its survival mechanism. 
Cylindrospermum stagnale isolated (and deposited in NRMCF 3001) from soil showed presence of four plasmids namely pCYLM01, pCYLM02, pCYLM03, and pCYLM04.
The following plasmids pCYLM01 and pCYLM02 were subjected to restriction digestion using HindIII restriction enzyme and cloned into pBlueScriptSK(-) vector.
The sequence of pCYLM01 contained 4 potential open reading frames (ORFs) that have amino acids in the range of 59-299. Among them, ORF1 shows high sequence homology to the bacterial replication initiator family protein as evident from BLASTP analysis.
The analysis of 4359 bp plasmid pCYLM02 sequence revealed 7 ORFs which are longer than 50 amino acids in length. The ORF2 of pCYLM02 has 243 amino acids and is represented in the plasmid sequence from 3045 to 3776 bp.
The ORF3 of pCYLM02 corresponds to the plasmid sequence from 2323 to 2976 and codes for a putative protein of 217 amino acids long. A number of small ORFs below 50 bp were also found in the sequence analysis.
Kenneth Hill