Abstract
AME Aquatic Microbial Ecology Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials AME 44:11-20 (2006) - doi:10.3354/ame044011 Extracellular enzyme activities in benthic cyanobacterial mats: comparison between nutrient- enriched and control sites in marshes of northern Belize Dagmara Sirová1,*, Jaroslav Vrba1,2, Eliska Rejmánková3 1University of South Bohemia, Faculty of Biology, Department of Ecology, Branisovská 38, Ceské Budejovice 370 05, Czech Republic2Biology Centre AS CR, Institute of Hydrology, Na Sádkách 7, Ceské Budejovice 370 05, Czech Republic3Department of Environmental Science and Policy, University of California Davis, One Shields Avenue, Davis 956 16, California, USA *Email: dagmara.sirova@tiscali.cz ABSTRACT: Cyanobacterial mats, an important component of the oligotrophic alkaline wetland ecosystems of the Caribbean, are sensitive to nutrient enrichment. In order to elucidate their role in nutrient cycling, we measured extracellular enzyme activities in cyanobacterial mats and underlying sediment exposed to a long-term effect of different salinities and nutrient enrichment. Activities of alkaline phosphatase, leucine-aminopeptidase, arylsulphatase, and β-glucosidase were measured fluorometrically. The distribution of phosphatase activity among different groups of microorganisms in the vertical structure of the mat was visualized using ELF®97 phosphate. The activity of all enzymes, except arylsulphatase, was localized mainly in the mat itself and was several times higher than in the underlying sediment. Phosphatase always exhibited the highest activity, followed by leucine-aminopeptidase, arylsulphatase and β-glucosidase. Phosphatase activity was significantly suppressed in P-addition plots under all salinity levels. The remaining enzymes were not significantly influenced by nutrient addition. Cyanobacteria, which formed most of the mat biomass, exhibited no phosphatase activity, with the exception of Chroococcus spp. Hence, we presume that the main sources of extracellular enzymes are different species of bacteria distributed in the mat and the mucilaginous sheaths of cyanobacteria. Sediment type, rather than salinity, seems to have an important influence on the extracellular enzyme production strategies. KEY WORDS: Alkaline phosphatase · Leucine-aminopeptidase · β-glucosidase · Arylsulphatase · Extracellular polymeric substances · Phosphorus Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in AME Vol. 44, No. 1. Online publication date: August 16, 2006 Print ISSN: 0948-3055; Online ISSN: 1616-1564 Copyright © 2006 Inter-Research.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
