TY - JOUR
T1 - Experimental identification and in silico prediction of bacterivory in green algae
AU - Bock, Nicholas A.
AU - Charvet, Sophie
AU - Burns, John
AU - Gyaltshen, Yangtsho
AU - Rozenberg, Andrey
AU - Duhamel, Solange
AU - Kim, Eunsoo
N1 - Funding Information:
Acknowledgements The authors are indebted to Colomban de Vargas, Ian Probert, and Daniel Vaulot for providing access to Roscoff Culture Collection (RCC) strains for preliminary feeding assays conducted at the RCC. We also thank Ashley Yang and Kaleigh Lukacs for assisting with green algal culturing; John Favate and Andres Salazar Estrada for conducting preliminary feeding assays using epi-fluorescence microscopy; and Andrew K Smith at the Microscopy Imaging Facility at the American Museum of Natural History for help with confocal work; and O. Roger Anderson for helpful comments on the manuscript. This work was supported by the NSF CAREER-1453639, NSF OCE-14580950, and Simons Foundation 382790 awards to EK, and NSF OCE-1458070 award to SD.
Publisher Copyright:
© 2021, The Author(s).
PY - 2021/7
Y1 - 2021/7
N2 - While algal phago-mixotrophs play a major role in aquatic microbial food webs, their diversity remains poorly understood. Recent studies have indicated several species of prasinophytes, early diverging green algae, to be able to consume bacteria for nutrition. To further explore the occurrence of phago-mixotrophy in green algae, we conducted feeding experiments with live fluorescently labeled bacteria stained with CellTracker Green CMFDA, heat-killed bacteria stained with 5-(4,6-dichlorotriazin-2-yl) aminofluorescein (DTAF), and magnetic beads. Feeding was detected via microscopy and/or flow cytometry in five strains of prasinophytes when provided with live bacteria: Pterosperma cristatum NIES626, Pyramimonas parkeae CCMP726, Pyramimonas parkeae NIES254, Nephroselmis pyriformis RCC618, and Dolichomastix tenuilepis CCMP3274. No feeding was detected when heat-killed bacteria or magnetic beads were provided, suggesting a strong preference for live prey in the strains tested. In parallel to experimental assays, green algal bacterivory was investigated using a gene-based prediction model. The predictions agreed with the experimental results and suggested bacterivory potential in additional green algae. Our observations underline the likelihood of widespread occurrence of phago-mixotrophy among green algae, while additionally highlighting potential biases introduced when using prey proxy to evaluate bacterial ingestion by algal cells.
AB - While algal phago-mixotrophs play a major role in aquatic microbial food webs, their diversity remains poorly understood. Recent studies have indicated several species of prasinophytes, early diverging green algae, to be able to consume bacteria for nutrition. To further explore the occurrence of phago-mixotrophy in green algae, we conducted feeding experiments with live fluorescently labeled bacteria stained with CellTracker Green CMFDA, heat-killed bacteria stained with 5-(4,6-dichlorotriazin-2-yl) aminofluorescein (DTAF), and magnetic beads. Feeding was detected via microscopy and/or flow cytometry in five strains of prasinophytes when provided with live bacteria: Pterosperma cristatum NIES626, Pyramimonas parkeae CCMP726, Pyramimonas parkeae NIES254, Nephroselmis pyriformis RCC618, and Dolichomastix tenuilepis CCMP3274. No feeding was detected when heat-killed bacteria or magnetic beads were provided, suggesting a strong preference for live prey in the strains tested. In parallel to experimental assays, green algal bacterivory was investigated using a gene-based prediction model. The predictions agreed with the experimental results and suggested bacterivory potential in additional green algae. Our observations underline the likelihood of widespread occurrence of phago-mixotrophy among green algae, while additionally highlighting potential biases introduced when using prey proxy to evaluate bacterial ingestion by algal cells.
UR - http://www.scopus.com/inward/record.url?scp=85101829715&partnerID=8YFLogxK
U2 - 10.1038/s41396-021-00899-w
DO - 10.1038/s41396-021-00899-w
M3 - Article
C2 - 33649548
AN - SCOPUS:85101829715
SN - 1751-7362
VL - 15
SP - 1987
EP - 2000
JO - ISME Journal
JF - ISME Journal
IS - 7
ER -