|   | 
Details
   web
Records
Author Hengst, M.B.; Andrade, S.; Gonzalez, B.; Correa, J.A.
Title (up) Changes in Epiphytic Bacterial Communities of Intertidal Seaweeds Modulated by Host, Temporality, and Copper Enrichment Type
Year 2010 Publication Microbial Ecology Abbreviated Journal Microb. Ecol.
Volume 60 Issue 2 Pages 282-290
Keywords
Abstract This study reports on the factors involved in regulating the composition and structure of bacterial communities epiphytic on intertidal macroalgae, exploring their temporal variability and the role of copper pollution. Culture-independent, molecular approaches were chosen for this purpose and three host species were used as models: the ephemeral Ulva spp. (Chlorophyceae) and Scytosiphon lomentaria (Phaeophyceae) and the long-living Lessonia nigrescens (Phaeophyceae). The algae were collected from two coastal areas in Northern Chile, where the main contrast was the concentration of copper in the seawater column resulting from copper-mine waste disposals. We found a clear and strong effect in the structure of the bacterial communities associated with the algal species serving as host. The structure of the bacterial communities also varied through time. The effect of copper on the structure of the epiphytic bacterial communities was significant in Ulva spp., but not on L. nigrescens. The use of 16S rRNA gene library analysis to compare bacterial communities in Ulva revealed that they were composed of five phyla and six classes, with approximately 35 bacterial species, dominated by members of Bacteroidetes (Cytophaga-Flavobacteria-Bacteroides) and alpha-Proteobacteria, in both non-polluted and polluted sites. Less common groups, such as the Verrucomicrobiae, were exclusively found in polluted sites. This work shows that the structure of bacterial communities epiphytic on macroalgae is hierarchically determined by algal species > temporal changes > copper levels.
Address [Hengst, Martha B.] Univ Antofagasta, Antofagasta Inst Renewable Resources, Antofagasta, Chile, Email: bernardo.gonzalez@uai.cl
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0095-3628 ISBN Medium
Area Expedition Conference
Notes WOS:000281981300003 Approved
Call Number UAI @ eduardo.moreno @ Serial 98
Permanent link to this record
 

 
Author Tapia, J.E.; Gonzalez, B.; Goulitquer, S.; Potin, P.; Correa, J.A.
Title (up) Microbiota Influences Morphology and Reproduction of the Brown Alga Ectocarpus sp Type
Year 2016 Publication Frontiers In Microbiology Abbreviated Journal Front. Microbiol.
Volume 7 Issue Pages 14 pp
Keywords microbiota; bacteria-algae interaction; Ectocarpus; bacterial isolate; algal morphology; exometabolome
Abstract Associated microbiota play crucial roles in health and disease of higher organisms. For macroalgae, some associated bacteria exert beneficial effects on nutrition, morphogenesis and growth. However, current knowledge on macroalgae microbiota interactions is mostly based on studies on green and red seaweeds. In this study, we report that when cultured under axenic conditions, the filamentous brown algal model Ectocarpus sp. loses its branched morphology and grows with a small ball like appearance. Nine strains of periphytic bacteria isolated from Ectocarpus sp. unialgal cultures were identified by 16S rRNA sequencing, and assessed for their effect on morphology, reproduction and the metabolites secreted by axenic Ectocarpus sp. Six of these isolates restored morphology and reproduction features of axenic Ectocarpus sp. Bacteria-algae co-culture supernatants, but not the supernatant of the corresponding bacterium growing alone, also recovered morphology and reproduction of the alga. Furthermore, colonization of axenic Ectocarpus sp. with a single bacterial isolate impacted significantly the metabolites released by the alga. These results show that the branched typical morphology and the individuals produced by Ectocarpus sp. are strongly dependent on the presence of bacteria, while the bacterial effect on the algal exometabolome profile reflects the impact of bacteria on the whole physiology of this alga.
Address [Tapia, Javier E.; Correa, Juan A.] Univ Paris 06, CNRS, Biol & Ecol Algae, Stn Biol Roscoff, Roscoff, France, Email: jcorrea@bio.puc.cl
Corporate Author Thesis
Publisher Frontiers Media Sa Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1664-302x ISBN Medium
Area Expedition Conference
Notes WOS:000370760000001 Approved
Call Number UAI @ eduardo.moreno @ Serial 589
Permanent link to this record
 

 
Author De la Iglesia, R.; Valenzuela-Heredia, D.; Pavissich, J.P.; Freyhoffer, S.; Andrade, S.; Correa, J.A.; Gonzalez, B.
Title (up) Novel polymerase chain reaction primers for the specific detection of bacterial copper P-type ATPases gene sequences in environmental isolates and metagenomic DNA Type
Year 2010 Publication Letters In Applied Microbiology Abbreviated Journal Lett. Appl. Microbiol.
Volume 50 Issue 6 Pages 552-562
Keywords ATPases; bacterial communities; copper resistance; metagenomic DNA; PCR primer pair
Abstract Aims: In the last decades, the worldwide increase in copper wastes release by industrial activities like mining has driven environmental metal contents to toxic levels. For this reason, the study of the biological copper-resistance mechanisms in natural environments is important. Therefore, an appropriate molecular tool for the detection and tracking of copper-resistance genes was developed. Methods and Results: In this work, we designed a PCR primer pair to specifically detect copper P-type ATPases gene sequences. These PCR primers were tested in bacterial isolates and metagenomic DNA from intertidal marine environments impacted by copper pollution. As well, T-RFLP fingerprinting of these gene sequences was used to compare the genetic composition of such genes in microbial communities, in normal and copper-polluted coastal environments. New copper P-type ATPases gene sequences were found, and a high degree of change in the genetic composition because of copper exposure was also determined. Conclusions: This PCR based method is useful to track bacterial copper-resistance gene sequences in the environment. Significance and Impact of the Study: This study is the first to report the design and use of a PCR primer pair as a molecular marker to track bacterial copper-resistance determinants, providing an excellent tool for long-term analysis of environmental communities exposed to metal pollution.
Address [Gonzalez, B.] Univ Adolfo Ibanez, Fac Ingn & Ciencia, Santiago 7941169, Chile, Email: bernardo.gonzalez@uai.cl
Corporate Author Thesis
Publisher Wiley-Blackwell Publishing, Inc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0266-8254 ISBN Medium
Area Expedition Conference
Notes WOS:000277417000002 Approved
Call Number UAI @ eduardo.moreno @ Serial 88
Permanent link to this record