View Abstract

AEROBIC ANOXYGENIC PHOTOTROPHIC BACTERIA IN COASTAL GULF OF MEXICO COMMUNITY SHIFTS UPON EXPOSURE TO MC 252 WATER ACCOMMODATED FRACTION AND DISPERSANT

Gulf of Mexico (GoM) coastal waters contain a diverse bacterial community, but anthropogenic inputs of crude oil components and dispersant can severely impact diversity. Aerobic Anoxygenic Phototrophic bacteria (AAP) are photoheterotrophic and their contribution to organic matter consumption may be greater than abundances would suggest. We hypothesized that AAP in a GoM coastal community are generalists, possibly increasing with anthropogenic inputs. The response following treatment with water accommodated fraction (WAF) of Louisiana sweet crude oil (MC 252), the dispersant Corexit, or a combination of both, was tested. Coastal GoM water in 64 L mesocosms was subjected to a 29 hr diel cycle or darkness. Upon WAF amendment, bacterial leucine incorporation increased 2 and 10-fold compared to the control in the light and dark, respectively. Addition of Corexit and Corexit plus WAF increased bacterial production by 4 and 10-fold in the light and dark treatments. Direct sunlight inhibits growth and photochemical reactions in sunlight increase inhibition of bacterial production. The response of AAP, enumerated by qPCR, was different than the community as a whole. With Corexit or Corexit plus WAF, AAP abundance increased by 3 and 5-fold in the light treatment; in the dark, AAP increased similarly. In contrast, WAF alone did not significantly increase the AAP abundance, suggesting that this group of bacteria responds differently than the remainder of the heterotrophic community. An analysis of the AAP bacterial subgroups in these treatments is currently being examined.

Authors

Waidner, L., University of West Florida, USA, lwaidner@uwf.edu

Matallana-Surget, S., University of Stirling, United Kingdom, sabine.matallanasurget@stir.ac.uk

Nigro, L., University of West Florida, USA, lnigro@uwf.edu

LeBaron, P., Observatoire Océanologique de Banyuls, France, philippe.lebaron@obs-banyuls.fr

Ederington0Hagy, M., University of West Florida, USA, mederingtonhagy@uwf.edu

Brock, M. L., University of West Florida, USA, mlb76@uwf.edu

Daniel, C., University of West Florida, USA, ced25@students.uwf.edu

Valek, J., University of West Florida, USA, jnv8@students.uwd.edu

Jeffrey, W. H., University of West Florida, USA, wjeffrey@uwf.edu

Details

Poster presentation

Session #:071
Date: 02/27/2017
Time: 11:00 - 12:00
Location: Poster/Exhibit Hall

Presentation is given by student: No

PosterID: 549