Dataset Information

Structural modification of LPS in colistin-resistant, KPC-producing Klebsiella pneumoniae.

ABSTRACT:

Background

Colistin resistance in Klebsiella pneumoniae typically involves inactivation or mutations of chromosomal genes mgrB, pmrAB or phoPQ, but data regarding consequent modifications of LPS are limited.

Objectives

To examine the sequences of chromosomal loci implicated in colistin resistance and the respective LPS-derived lipid A profiles using 11 pairs of colistin-susceptible and -resistant KPC-producing K. pneumoniae clinical strains.

Methods

The strains were subjected to high-throughput sequencing with Illumina HiSeq. The mgrB gene was amplified by PCR and sequenced. Lipid profiles were determined using MALDI-TOF MS.

Results

All patients were treated with colistimethate prior to the isolation of colistin-resistant strains (MIC >2 mg/L). Seven of 11 colistin-resistant strains had deletion or insertional inactivation of mgrB. Three strains, including one with an mgrB deletion, had non-synonymous pmrB mutations associated with colistin resistance. When analysed by MALDI-TOF MS, all colistin-resistant strains generated mass spectra containing ions at m/z 1955 and 1971, consistent with addition of 4-amino-4-deoxy-l-arabinose (Ara4N) to lipid A, whereas only one of the susceptible strains displayed this lipid A phenotype.

Conclusions

The pathway to colistin resistance in K. pneumoniae primarily involves lipid A modification with Ara4N in clinical settings.

SUBMITTER: Leung LM

PROVIDER: S-EPMC5890713 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Publications

Structural modification of LPS in colistin-resistant, KPC-producing Klebsiella pneumoniae.

Leung Lisa M LM Cooper Vaughn S VS Rasko David A DA Guo Qinglan Q Pacey Marissa P MP McElheny Christi L CL Mettus Roberta T RT Yoon Sung Hwan SH Goodlett David R DR Ernst Robert K RK Doi Yohei Y

The Journal of antimicrobial chemotherapy 20171101 11

<h4>Background</h4>Colistin resistance in Klebsiella pneumoniae typically involves inactivation or mutations of chromosomal genes mgrB, pmrAB or phoPQ, but data regarding consequent modifications of LPS are limited.<h4>Objectives</h4>To examine the sequences of chromosomal loci implicated in colistin resistance and the respective LPS-derived lipid A profiles using 11 pairs of colistin-susceptible and -resistant KPC-producing K. pneumoniae clinical strains.<h4>Methods</h4>The strains were subject ...[more]

PMID: 28961916

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Dataset Information

Structural modification of LPS in colistin-resistant, KPC-producing Klebsiella pneumoniae.

Background

Objectives

Methods

Results

Conclusions

Publications

Structural modification of LPS in colistin-resistant, KPC-producing Klebsiella pneumoniae.

Similar Datasets

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