title: Characterization of heterotrophic prokaryote subgroups in the Sfax coastal solar salterns by combining flow cytometry cell sorting and phylogenetic analysis.
abstract: Here, we combined flow cytometry (FCM) and phylogenetic analyses after cell sorting to characterize the dominant groups of the prokaryotic assemblages inhabiting two ponds of increasing salinity: a crystallizer pond (TS) with a salinity of 390 g/L, and the non-crystallizer pond (M1) with a salinity of 200 g/L retrieved from the solar saltern of Sfax in Tunisia. As expected, FCM analysis enabled the resolution of high nucleic acid content (HNA) and low nucleic acid content (LNA) prokaryotes. Next, we performed a taxonomic analysis of the bacterial and archaeal communities comprising the two most populated clusters by phylogenetic analyses of 16S rRNA gene clone library. We show for the first time that the presence of HNA and LNA content cells could also be extended to the archaeal populations. Archaea were detected in all M1 and TS samples, whereas representatives of Bacteria were detected only in LNA for M1 and HNA for TS. Although most of the archaeal sequences remained undetermined, other clones were most frequently affiliated to Haloquadratum and Halorubrum. In contrast, most bacterial clones belonged to the Alphaproteobacteria class (Phyllobacterium genus) in M1 samples and to the Bacteroidetes phylum (Sphingobacteria and Salinibacter genus) in TS samples.
authors.affiliation: Laboratoire de Microbiologie, Faculté des Sciences de Sfax, B.P. 802, 3000, Sfax, Tunisia.
authors.forename: Hana
authors.initials: H
authors.lastname: Trigui
authors.forename: Salma
authors.initials: S
authors.lastname: Masmoudi
authors.forename: Céline
authors.initials: C
authors.lastname: Brochier-Armanet
authors.forename: Aude
authors.initials: A
authors.lastname: Barani
authors.forename: Gérald
authors.initials: G
authors.lastname: Grégori
authors.forename: Michel
authors.initials: M
authors.lastname: Denis
authors.forename: Sam
authors.initials: S
authors.lastname: Dukan
authors.forename: Sami
authors.initials: S
authors.lastname: Maalej
mesh_terms: D020561:Alphaproteobacteria / Q000145:classification; D001105:Archaea / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D001419:Bacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D041963:Bacteroidetes / Q000145:classification; D044822:Biodiversity; D019641:DNA, Archaeal / Q000302:isolation & purification; D004269:DNA, Bacterial / Q000302:isolation & purification; D005434:Flow Cytometry; D055352:Halorubrum / Q000145:classification; D052836:Heterotrophic Processes; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D021521:Ribotyping; D054712:Salinity; D045249:Sphingobacterium / Q000145:classification; D014416:Tunisia; D014867:Water / Q000737:chemistry*; D014871:Water Microbiology
chemical_list: D019641:DNA, Archaeal; D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S; D014867:Water