title: Modelled microgravity cultivation modulates N-acylhomoserine lactone production in Rhodospirillum rubrum S1H independently of cell density.
abstract: The photosynthetic alphaproteobacterium Rhodospirillum rubrum S1H is part of the Micro-Ecological Life Support System Alternative (MELiSSA) project that is aiming to develop a closed life support system for oxygen, water and food production to support human life in space in forthcoming long-term space exploration missions. In the present study, R. rubrum S1H was cultured in a rotating wall vessel (RWV), simulating partial microgravity conditions on Earth. The bacterium showed a significant response to cultivation in simulated microgravity at the transcriptomic, proteomic and metabolic levels. In simulated microgravity conditions three N-acyl-l-homoserine lactones (C10-HSL, C12-HSL and 3-OH-C14-HSL) were detected in concentrations that were twice those detected under normal gravity, while no differences in cell density was detected. In addition, R. rubrum cultivated in modelled microgravity showed higher pigmentation than the normal gravity control, without change in culture oxygenation. When compared to randomized microgravity cultivation using a random positioning machine, significant overlap for the top differentially expressed genes and proteins was observed. Cultivation in this new artificial environment of simulated microgravity showed new properties of this well-known bacterium, including its first, to our knowledge, complete quorum-sensing-related N-acylhomoserine lactone profile.
authors.affiliation: Unit for Microbiology, Belgian Nuclear Research Centre (SCK•CEN), Mol, Belgium.
authors.forename: Felice
authors.initials: F
authors.lastname: Mastroleo
authors.affiliation: Unit for Microbiology, Belgian Nuclear Research Centre (SCK•CEN), Mol, Belgium.
authors.forename: Rob
authors.initials: R
authors.lastname: Van Houdt
authors.affiliation: School of Molecular Medical Sciences, University of Nottingham, Nottingham, UK.
authors.forename: Steve
authors.initials: S
authors.lastname: Atkinson
authors.affiliation: Unit for Microbiology, Belgian Nuclear Research Centre (SCK•CEN), Mol, Belgium.
authors.forename: Max
authors.initials: M
authors.lastname: Mergeay
authors.affiliation: Unit for Microbiology, Belgian Nuclear Research Centre (SCK•CEN), Mol, Belgium.
authors.forename: Larissa
authors.initials: L
authors.lastname: Hendrickx
authors.affiliation: Research Institute of Biosciences, Proteomic and Microbiology Laboratory, Université de Mons, Mons, Belgium.
authors.forename: Ruddy
authors.initials: R
authors.lastname: Wattiez
authors.affiliation: Unit for Microbiology, Belgian Nuclear Research Centre (SCK•CEN), Mol, Belgium.
authors.forename: Natalie
authors.initials: N
authors.lastname: Leys
mesh_terms: D054742:Acyl-Butyrolactones / Q000378:metabolism*; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D055432:Metabolomics; D010860:Pigments, Biological / Q000378:metabolism; D020543:Proteome / Q000032:analysis; D053038:Quorum Sensing; D012247:Rhodospirillum rubrum / Q000166:cytology / Q000502:physiology*; D014893:Weightlessness
chemical_list: D054742:Acyl-Butyrolactones; D010860:Pigments, Biological; D020543:Proteome