Please use this identifier to cite or link to this item:
Title: Proportion of prokaryotes enumerated as viruses by epifluorescence microscopy
Author: Mendes, Carlos
Santos, Luísa
Cunha, Ângela
Gomez, Newton C. M.
Almeida, Adelaide
Keywords: Epifluorescence microscopy
Issue Date: 2014
Publisher: Springer
Abstract: It is well known that there are prokaryotes small in size (e.g. ultra-microprokaryotes) that pass through a 0.2-mu m filter. As bacterial and viral abundances are determined by epifluorescence microscopy and the differentiation between them is based on particle size, some bacteria can be erroneously enumerated as viruses, namely in marine waters where bacteria are small. However, there is no information on the proportion of prokaryotes that could be misidentified as viruses by epifluorescence microscopy. In this work, we assessed, in water samples collected in the estuarine system Ria de Aveiro (Portugal), the proportion of prokaryotes that could be counted as viruses by the current widespread epifluorescence microscopy and, for the first time, by fluorescence in situ hybridization (FISH). The total number of particles was determined on membranes of 0.2 and 0.02 mu m after staining with 4',6-diamidino-2-phenylindole (DAPI), and the number of prokaryotes (Bacteria and Archaea) was determined by FISH for both pore size membranes. The results show that, in the marine zone of the estuarine system, 28 % of particles enumerated as virus-like particles were prokaryotes, but, in the brackish water zone, only 13 % of the particles counted as viruses were actually prokaryotic cells. Epifluorescence microscopy overestimates viral abundance, and also the ratio viruses:prokaryotes, and this error must be taken into consideration because it can vary significantly within a system. In fact, in the marine zone of an estuarine system, the overestimation of viral abundance can be twice as high as in the brackish water zone.
Peer review: yes
DOI: 10.1007/s13213-013-0713-y
ISSN: 1590-4261
Appears in Collections:CESAM - Artigos
DBio - Artigos

Files in This Item:
File Description SizeFormat 
Mendes et al. - 2014 - Proportion of prokaryotes enumerated as viruses by.pdf242.03 kBAdobe PDFrestrictedAccess

Formato BibTex MendeleyEndnote Degois 

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.