Dataset Information

Expression and evolutionary patterns of mycobacteriophage D29 and its temperate close relatives.

ABSTRACT: BACKGROUND:Mycobacteriophages are viruses that infect Mycobacterium hosts. A large collection of phages known to infect the same bacterial host strain - Mycobacterium smegmatis mc2155 - exhibit substantial diversity and characteristically mosaic architectures. The well-studied lytic mycobacteriophage D29 appears to be a deletion derivative of a putative temperate parent, although its parent has yet to be identified. RESULTS:Here we describe three newly-isolated temperate phages - Kerberos, Pomar16 and StarStuff - that are related to D29, and are predicted to be very close relatives of its putative temperate parent, revealing the repressor and additional genes that are lost in D29. Transcriptional profiles show the patterns of both lysogenic and lytic gene expression and identify highly-expressed, abundant, stable, small non-coding transcripts made from the Pleft early lytic promoter, and which are toxic to M. smegmatis. CONCLUSIONS:Comparative genomics of phages D29, Kerberos, Pomar16 and StarStuff provide insights into bacteriophage evolution, and comparative transcriptomics identifies the pattern of lysogenic and lytic expression with unusual features including highly expressed, small, non-coding RNAs.

SUBMITTER: Dedrick RM

PROVIDER: S-EPMC5712189 | biostudies-literature | 2017 Dec

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Expression and evolutionary patterns of mycobacteriophage D29 and its temperate close relatives.

Dedrick Rebekah M RM Mavrich Travis N TN Ng Wei L WL Hatfull Graham F GF

BMC microbiology 20171202 1

<h4>Background</h4>Mycobacteriophages are viruses that infect Mycobacterium hosts. A large collection of phages known to infect the same bacterial host strain - Mycobacterium smegmatis mc<sup>2</sup>155 - exhibit substantial diversity and characteristically mosaic architectures. The well-studied lytic mycobacteriophage D29 appears to be a deletion derivative of a putative temperate parent, although its parent has yet to be identified.<h4>Results</h4>Here we describe three newly-isolated temperat ...[more]

PMID: 29197343

Similar Datasets

Project description:Emergence of antibiotic resistance in pathogenic Mycobacterium tuberculosis (Mtb) has elevated tuberculosis to a serious global threat, necessitating alternate solutions for its eradication. D29 mycobacteriophage can infect and kill several mycobacterial species including Mtb. It encodes an endolysin LysA to hydrolyze host bacteria peptidoglycan for progeny release. We previously showed that out of the two catalytically active domains of LysA [N-terminal domain (NTD) and lysozyme-like domain], NTD, when ectopically expressed in Mycobacterium smegmatis (Msm), is able to kill the bacterium nearly as efficiently as full-length LysA. Here, we dissected the functioning of NTD to develop it as a phage-derived small molecule anti-mycobacterial therapeutic. We performed a large-scale site-directed mutagenesis of the conserved residues in NTD and examined its structure, stability, and function using molecular dynamic simulations coupled with biophysical and biochemical experiments. Our data show that NTD functions as a putative cysteine peptidase with a catalytic triad composed of Cys41, His112, and Glu137, acting as nucleophile, base, and acid, respectively, and showing characteristics similar to the NlpC/P60 family of cysteine peptidases. Additionally, our peptidoglycan hydrolysis assays suggested that NTD hydrolyzes only mycobacterial peptidoglycan and does not act on Gram-positive and Gram-negative bacterial peptidoglycans. More importantly, the combined activity of exogenously added NTD and sub-lethal doses of anti-mycobacterial drugs kills Msm in vitro and exhibits disruption of pre-formed mycobacterial biofilm. We additionally show that NTD treatment increases the permeability of antibiotics in Msm, which reduces the minimum inhibitory concentration of the antibiotics. Collectively, we present NTD as a promising phage-derived therapeutic against mycobacteria.IMPORTANCEMycobacteriophages are the viruses that use mycobacteria as host for their progeny production and, in the process, kill them. Mycobacteriophages are, therefore, considered as promising alternatives to antibiotics for killing pathogenic Mycobacterium tuberculosis. The endolysin LysA produced by mycobacteriophage D29 plays an important role in host cell lysis and virion release. Our work presented here highlights the functioning of LysA's N-terminal catalytic domain (NTD) in order to develop it as phage-derived small molecule therapeutics. We show that combined treatment of exogenously added NTD and sub-lethal doses of anti-mycobacterial drugs kills M. smegmatis, shows synergism by reducing the minimum inhibitory concentration of these antibiotics, and exhibits disruption of pre-formed mature biofilm. These outcomes and our detailed biochemical and biophysical dissection of the protein further pave the way toward engineering and development of NTD as a promising therapeutic against mycobacterial infections such as tuberculosis.

Dataset Information

Expression and evolutionary patterns of mycobacteriophage D29 and its temperate close relatives.

Publications

Expression and evolutionary patterns of mycobacteriophage D29 and its temperate close relatives.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets