A metagenome for lacustrine Cladophora (Cladophorales) reveals remarkable diversity of eukaryotic epibionts and genes relevant to materials cycling. Issue 3 (4th May 2015)

• Record Type: Journal Article
• Authors: Graham, Linda E.; Knack, Jennifer J.; Graham, Melissa E.; Graham, James M.; Zulkifly, Shahrizim; Müller, K.
• Is Part Of: Journal of phycology. Volume 51:Issue 3(2015)
• Page Start: 408
• Page End: 418
• Publication Date: 2015-05-04
• Subjects: Algae -- Periodicals; 579.8
• DOI: 10.1111/jpy.12296
• Languages: English
• ISSNs: 0022-3646

Abstract

<abstract abstract-type="main" id="jpy12296-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <p>Periphyton dominated by the cellulose‐rich filamentous green alga <italic>Cladophora</italic> forms conspicuous growths along rocky marine and freshwater shorelines worldwide, providing habitat for diverse epibionts. Bacterial epibionts have been inferred to display diverse functions of biogeochemical significance: N‐fixation and other redox reactions, phosphorus accumulation, and organic degradation. Here, we report taxonomic diversity of eukaryotic and prokaryotic epibionts and diversity of genes associated with materials cycling in a <italic>Cladophora</italic> metagenome sampled from Lake Mendota, Dane Co., WI, USA, during the growing season of 2012. A total of 1, 060 distinct 16S, 173 18S, and 351 28S rRNA operational taxonomic units, from which >220 genera or species of bacteria (~60), protists (~80), fungi (6), and microscopic metazoa (~80), were distinguished with the use of reference databases. We inferred the presence of several algal taxa generally associated with marine systems and detected <italic>Jaoa</italic>, a freshwater periphytic ulvophyte previously thought endemic to China. We identified six distinct <italic>nifH</italic> gene sequences marking nitrogen fixation, >25 bacterial and eukaryotic cellulases relevant to sedimentary C‐cycling and technological applications, and genes encoding enzymes in aerobic and anaerobic pathways for vitamin B<sub>12</sub> biosynthesis. These results emphasize the importance of <italic>Cladophora</italic> in providing habitat for microscopic metazoa, fungi, protists, and bacteria that are often inconspicuous, yet play important roles in ecosystem biogeochemistry.</p> </abstract>