TitleSpecific activity of cell-surface acid phosphatase in different bacterioplankton morphotypes in an acidified mountain lake
Publication TypeJournal Article
Year of Publication2006
AuthorsNedoma, J, Vrba, J
JournalEnvironmental Microbiology

Activity of extracellular acid phosphatases was measured at single-cell level in bacterioplankton groups defined by their morphology and size, in acidified mountain Lake Certovo, during the 2003 season, with a method based on use of the substrate ELF97 phosphate which provides fluorescent precipitates upon hydrolysis by phosphatases. The bacterial cell-associated precipitates were quantified by image analysis. A specific, conspicuous, apparently homogeneous morphotype of curved cells of similar to 5 mu m average length, despite its low total biomass (average of 4%), contributed significantly (in average by 31%) to the total bacterioplankton phosphatase activity in Lake Certovo (ranging from 1.0 to 12.7 mu mol l(-1) h(-1), using ELF97 phosphate as a substrate). Bacterial filaments (> 10 mu m), although comprising in average 85% of bacterioplankton biomass, contributed to the total bacterioplankton activity only by 45%. Biomass-specific activity of extracellular (cell-surface) phosphatases of the main bacterioplankton morphotypes increased in the order filaments