title: Vertical distribution of bacterioplankton in Lake Averno in relation to water chemistry.
abstract: The effects of environmental factors on bacterioplankton distribution along the water column of Lake Averno (Naples, Italy) have been investigated by means of denaturing gradient gel electrophoresis (DGGE) of polymerase chain reaction (PCR)-amplified 16S rRNA gene fragments, and multivariate analysis applied to molecular data and physico-chemical parameters. Bacterial richness, estimated from DGGE profiles, remains constant throughout the water column, whereas archaeal richness increases with depth. Moreover, archaeal richness was significantly correlated to most of the measured abiotic variables, whereas bacterial richness did not. Analysis of sequences from DGGE bands revealed that the dominant bacterial populations belong to Alphaproteobacteria, Betaproteobacteria, Deltaproteobacteria, Bacteroidetes and Firmicutes, whereas sequences of the archaeal DGGE bands are affiliated to Methanomicrobiales and Methanosarcinales orders. Moreover, bacterial sequences affiliated to Proteobacteria and Bacteroidetes do not group closely to typical freshwater lineages/clades/tribes within these phyla. Bacterioplankton distribution along the water column was apparently correlated with the vertical gradient of physico-chemical parameters as a statistically significant relationship between most of them with grouping of specific taxonomic units was observed.
authors.affiliation: ENEA C. R. Casaccia, Technical Unit for Sustainable Development and Innovation of Agroindustrial System, Rome, Italy.
authors.forename: Patrizia
authors.initials: P
authors.lastname: Paganin
authors.forename: Luigi
authors.initials: L
authors.lastname: Chiarini
authors.forename: Annamaria
authors.initials: A
authors.lastname: Bevivino
authors.forename: Claudia
authors.initials: C
authors.lastname: Dalmastri
authors.forename: Alessio
authors.initials: A
authors.lastname: Farcomeni
authors.forename: Giulio
authors.initials: G
authors.lastname: Izzo
authors.forename: Antonella
authors.initials: A
authors.lastname: Signorini
authors.forename: Cristiano
authors.initials: C
authors.lastname: Varrone
authors.forename: Silvia
authors.initials: S
authors.lastname: Tabacchioni
mesh_terms: D001105:Archaea / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D001419:Bacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D044822:Biodiversity; D058645:Denaturing Gradient Gel Electrophoresis; D007558:Italy; D060106:Lakes / Q000737:chemistry / Q000382:microbiology*; D010802:Phylogeny; D010933:Plankton / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D016133:Polymerase Chain Reaction; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D017422:Sequence Analysis, DNA; D014867:Water / Q000737:chemistry; D014871:Water Microbiology
chemical_list: D012336:RNA, Ribosomal, 16S; D014867:Water