@Article{Weidenbach_Nickel_Neve-MetSV_novel_archa-2017,
  author =	 {Weidenbach, Katrin and Nickel, Lisa and Neve, Horst and 
                  Alkhnbashi, Omer S. and Kunzel, Sven and Kupczok, Anne and 
                  Bauersachs, Thorsten and Cassidy, Liam and Tholey, Andreas 
                  and Backofen, Rolf and Schmitz, Ruth A.},
  title =	 {{MetSV}, a novel archaeal lytic virus targeting 
                  {Methanosarcina} strains},
  journal =	 {J Virol},
  year =	 {2017},
  volume =	 {},
  number =	 {},
  pages =	 {},
  user =	 {alkhanbo},
  pmid =	 {28878086},
  doi = 	 {10.1128/JVI.00955-17},
  issn = 	 {1098-5514},
  issn = 	 {0022-538X},
  abstract =	 {A novel archaeal lytic virus targeting species of the genus 
                  Methanosarcina was isolated using Methanosarcina mazei 
                  strain Go1 as host. Due to its spherical morphology the 
                  virus was designated Methanosarcinaspherical virus (MetSV). 
                  Molecular analysis demonstrated that MetSV contains double 
                  stranded linear DNA with a genome size of 10,567 bp 
                  containing 22 open reading frames (ORFs) all oriented in the 
                  same direction. Functions were predicted for some of these 
                  ORFs, i. e. like DNA polymerase, ATPase, DNA-binding 
                  protein, as well as envelope (structural) protein. 
                  MetSV-derived spacers in CRISPR loci were detected in 
                  several published Methanosarcina draft genomes using 
                  bioinformatic tools, revealing the potential PAM motif 
                  (TTA/T). Transcription and expression of several predicted 
                  viral ORFs were validated by RT-PCR, PAGE analysis and LC-MS 
                  based proteomics. Analysis of core lipids by APCI mass 
                  spectrometry showed that MetSV and M. mazei both contain 
                  archaeol and glycerol dialkyl glycerol tetraether without 
                  cyclopentane moiety (GDGT-0). The MetSV host range is 
                  limited to Methanosarcina strains growing as single cells 
                  (M. mazei, M. bakeri and M. soligelidi). In contrast, 
                  strains growing as sarcina-like aggregates were apparently 
                  protected from infection. Heterogeneity related to 
                  morphology phases in M. mazei cultures allowed acquisition 
                  of resistance to MetSV after challenge by growing as 
                  sarcina-like aggregates. CRISPR/Cas mediated resistance was 
                  excluded since neither of the two CRISPR arrays showed 
                  MetSV-derived spacer acquisition. Based on these findings, 
                  we propose that changing the morphology from single cells to 
                  sarcina-like aggregates upon rearrangement of the envelope 
                  structure prevents infection and subsequent lysis by 
                  MetSV.IMPORTANCE Methanoarchaea are among the most abundant 
                  organisms on the planet since they are present in high 
                  numbers in major anaerobic environments. They convert 
                  various carbon sources e.g. acetate, methylamines or 
                  methanol to methane and carbon dioxide, thus they have a 
                  significant impact on the emission of major greenhouse 
                  gases. Today very little is known about viruses specifically 
                  infecting methanoarchaea, which most probably impact the 
                  abundance of methanoarchaea in microbial consortia. Here we 
                  characterize the first identified Methanosarcina infecting 
                  virus (MetSV) and show a mechanism for acquiring resistance 
                  against MetSV. Based on our results we propose that growth 
                  as sarcina-like aggregates prevents infection and subsequent 
                  lysis. These findings allow new insights into virus-host 
                  relationship in methanogenic community structures, their 
                  dynamics and their phase heterogeneity. Moreover, the 
                  availability of a specific virus provides new possibilities 
                  to deepen our knowledge on defence mechanisms of potential 
                  hosts and offers tools for genetic manipulation.}
}