title: Colonization and release processes of viruses and prokaryotes on artificial marine macroaggregates.
abstract: Marine organic aggregates are sites of high of viral accumulation; however, still little is known about their colonization processes and interactions with their local bacterial hosts. By taking advantage of a novel approach (paramagnetic functionalized microsphere method) to create and incubate artificial macroaggregates, we examined the small-scale movements of viruses and bacteria between such marine snow particles and the surrounding water. The examination of the codynamics of both free-living and attached viral and bacterial abundance, over 12 hours of incubation in virus-free water, suggests that aggregates are rather comparable to viral factories than to viral traps where a significant part of the virions production might be locally diverted to the water column. Also, the near-zero proportion of lysogenized cells measured in aggregates after mitomycin-C induction seems to indicate that lysogeny is not a prominent viral reproduction pathway in organic aggregates where most viruses might rather be virulent. Finally, we hypothesize that, contrary to bacteria, which can use both strong attachment and detachment from aggregates (two-way motion of bacteria), the adsorption of planktonic viruses appears to be numerically negligible compared to their massive export from the aggregates into the water column (one-way motion of viruses).
authors.affiliation: IRD, UMR 9190 MARBEC, 34095 Montpellier, France yvan.bettarel@ird.fr.
authors.forename: Yvan
authors.initials: Y
authors.lastname: Bettarel
authors.affiliation: Takuvik Joint International Laboratory, University Laval, Québec G1V 0A6, Canada.
authors.forename: Chiaki
authors.initials: C
authors.lastname: Motegi
authors.affiliation: CNRS, UMR 7093, LOV, Observatoire Océanologique, 06230 Villefranche-sur-Mer, France Sorbonne Universités, UPMC, Université Paris 06, UMR 7093, LOV, Observatoire Océanologique, 06230 Villefranche-sur-Mer, France.
authors.forename: Markus G
authors.initials: MG
authors.lastname: Weinbauer
authors.affiliation: CNRS, UMR 7093, LOV, Observatoire Océanologique, 06230 Villefranche-sur-Mer, France Sorbonne Universités, UPMC, Université Paris 06, UMR 7093, LOV, Observatoire Océanologique, 06230 Villefranche-sur-Mer, France Aix Marseille Université, CNRS/INSU, Université de Toulon, IRD, Mediterranean Institute of Oceanography (MIO) UM 110, 13288, Marseille, France.
authors.forename: Xavier
authors.initials: X
authors.lastname: Mari
mesh_terms: D059001:Aquatic Organisms / Q000302:isolation & purification* / Q000821:virology*; D001419:Bacteria / Q000302:isolation & purification* / Q000821:virology*; D001435:Bacteriophages / Q000254:growth & development* / Q000302:isolation & purification*; D017753:Ecosystem; D059013:Microbial Consortia; D012623:Seawater / Q000382:microbiology / Q000821:virology
keywords: aggregates; bacteria; ecology; seawater; viruses