Composition and activity of beta-Proteobacteria ammonia-oxidizing communities associated with intertidal rocky biofilms and sediments of the Douro River estuary, Portugal

• Type: Article in International Scientific Journal
• Date: 2007

Authors

Magalhaes, C (Author) Other; Bano, N (Author) Other; Wiebe, WJ (Author) Other; Hollibaugh, JT (Author) Other; Adriano Bordalo (Author) ICBAS

Journal

Title: JOURNAL OF APPLIED MICROBIOLOGY

Vol. 103

Pages: 1239-1250

ISSN: 1364-5072

Indexing

ISI Web of Knowledge - 16 Citations

Scopus - 20 Citations

Other information

Authenticus ID: P-004-768

DOI: 10.1111/j.1365-2672.2007.03390.x

Abstract (EN): Aims: To characterize the phylogenetic composition of ammonia-oxidizing bacteria (AOB) of the beta-subclass of the class Proteobacteria in intertidal sediment and rocky biofilms of the Douro estuary, and evaluate relationships with environmental variables and N-biogeochemistry. Methods and Results: Cluster analysis of denaturing gradient gel electrophoresis profiles showed differences in beta-Proteobacteria AOB assemblage composition between rocky biofilms and sediments. All sequences obtained from intertidal rocky biofilm sites exhibited phylogenetic affinity to Nitrosomonas sp. lineages, whereas a majority of the sequences from the sediment sites were most similar to marine Nitrosospira cluster 1. Hierarchical cluster analysis based on environmental variables identified two main groups of samples. The first contained samples from rocky biofilm sites characterized by high concentrations of NO2- and NH4+, and high organic matter and chlorophyll a content. The second group contained all of the sediment samples; these sites were characterized by lower values for the variables above. In addition, rocky biofilm sites exhibited higher nitrification rates. Conclusions: Intersite differences in environmental and/or physical conditions led to the selection of different populations of beta-Proteobacteria AOB, supporting different magnitudes of N-cycling regimes. Significance and Impact of the Study: This study represents an important step in establishing the influence of environmental factors on the distribution of beta-Proteobacteria AOB with possible consequences for N-biogeochemistry.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 12