Sunday, 19 October 2014

Entire genome of a Klebsiella pneumoniae strain sequenced

Microbiologists, for the first time, recently sequenced the entire genome of a Klebsiella pneumoniae strain, encoding New Delhi Metallo-beta-lactamase (NDM-1).

Assembling an entire genome is like putting together a puzzle. Klebsiella pneumoniae turned out to have one large chromosome and four plasmids, small DNA molecules physically separate from and able to replicate independently of the bacterial cell's chromosomal DNA. Plasmids often carry antibiotic resistant genes and other defense mechanisms.

The researchers discovered their Klebsiella pneumoniae bacteria encoded 34 separate enzymes of antibiotic resistance, as well as efflux pumps that move compounds out of cells, and mutations in chromosomal genes that are expected to confer resistance. They also identified several mechanisms that allow cells to mobilize resistance genes, both within a single cell and between cells.

For further details, see:

Corey M. Hudson, Zachary W. Bent, Robert J. Meagher, Kelly P. Williams. Resistance Determinants and Mobile Genetic Elements of an NDM-1-Encoding Klebsiella pneumoniae Strain. PLoS ONE, 2014; 9 (6): e99209 DOI: 10.1371/journal.pone.0099209

Posted by Tim Sandle