title: Life without a cell membrane: challenging the specificity of bacterial endophytes within Bryopsis (Bryopsidales, Chlorophyta).
abstract: BACKGROUND
  The siphonous green macroalga Bryopsis has some remarkable characteristics. Besides hosting a rich endophytic bacterial flora, Bryopsis also displays extraordinary wound repair and propagation mechanisms. This latter feature includes the formation of protoplasts which can survive in the absence of a cell membrane for several minutes before regenerating into new individuals. This transient 'life without a membrane' state, however, challenges the specificity of the endophytic bacterial communities present and raises the question whether these bacteria are generalists, which are repeatedly acquired from the environment, or if there is some specificity towards the Bryopsis host.
  
  
  RESULTS
  To answer this question, we examined the temporal stability and the uniqueness of endobiotic bacterial communities within Bryopsis samples from the Mexican west coast after prolonged cultivation. DGGE analysis revealed that Bryopsis endophytic bacterial communities are rather stable and clearly distinct from the epiphytic and surrounding cultivation water bacterial communities. Although these endogenous communities consist of both facultative and obligate bacteria, results suggest that Bryopsis owns some intrinsic mechanisms to selectively maintain and/or attract specific bacteria after repeated wounding events in culture.
  
  
  CONCLUSIONS
  This suggests that Bryopsis algae seem to master transient stages of life without a cell membrane well as they harbor specific--and possibly ecological significant--endophytic bacteria.
authors: Laboratory of Microbiology, Department of Biochemistry and Microbiology, Ghent University, K,L, Ledeganckstraat 35, 9000 Ghent, Belgium. Joke.Hollants@UGent.be
authors: Joke
authors: J
authors: Hollants
authors: Helen
authors: H
authors: Decleyre
authors: Frederik
authors: F
authors: Leliaert
authors: Olivier
authors: O
authors: De Clerck
authors: Anne
authors: A
authors: Willems
mesh_terms: D001419:Bacteria / Q000235:genetics / Q000254:growth & development*; D002462:Cell Membrane / Q000502:physiology*; D000460:Chlorophyta / Q000382:microbiology* / Q000502:physiology*; D004269:DNA, Bacterial / Q000235:genetics; D058645:Denaturing Gradient Gel Electrophoresis; D060026:Endophytes / Q000254:growth & development*; D011523:Protoplasts / Q000502:physiology; D017422:Sequence Analysis, DNA; D014871:Water Microbiology
chemical_list: D004269:DNA, Bacterial