Isolation and Purification of Viruses Infecting Cyanobacteria Using a Liquid Bioassay Approach   

Reviewed by
Anonymous reviewer
Download PDF How to cite Favorites Q&A Share your feedback Cited by

In this protocol

Original research article

A brief version of this protocol appeared in:
May 2016


The following protocol describes the isolation and purification of viruses infecting cyanobacteria using a liquid bioassay approach. Viruses infecting cyanobacteria are also known as cyanophages. This protocol was written specifically for the isolation of cyanophages infecting freshwater cyanobacteria particularly, cyanobacteria that cannot be cultured on solid media. The use of a clonal cyanobacterial culture is recommended for the isolation of viruses. Growth conditions (i.e., media, light cycle and temperature) should be modified based on the host of interest.

Keywords: Virus isolation, Virus purification, Aquatic microbiology, Cyanophage, Cyanobacteria, MPN assay, Liquid bioassay


Cyanobacteria are important phototrophs in both marine and freshwater systems. As other aquatic microorganisms, cyanobacteria are subject to viral infection (Suttle, 2000). For instance, in marine coastal regions, titers of viruses infecting Synechococcus spp. can reach up to 105 ml-1 and differ based on temperature, salinity and host abundance (Suttle and Chan, 1993; Waterbury and Valois, 1993). Despite the ecological importance of cyanobacteria and their viruses (also known as cyanophages), only a small number of viruses have been isolated from only a limited number of cyanobacterial strains. Consequently, it is of great interest to isolate new viruses by screening with new strains of cyanobacteria. The following protocol is relevant for both marine and freshwater systems but the example given below will focus on the isolation and purification of viruses infecting freshwater cyanobacteria (Chénard et al., 2015). The advantage of the liquid bioassay method over published protocols using solid substrate, is the opportunity to target cyanobacteria that cannot tolerate the higher temperatures often employed with the plaque assay method or cannot grow on solid media.

Copyright: © 2018 The Authors; exclusive licensee Bio-protocol LLC.
How to cite: Chénard, C. and Chan, A. M. (2018). Isolation and Purification of Viruses Infecting Cyanobacteria Using a Liquid Bioassay Approach. Bio-protocol 8(2): e2691. DOI: 10.21769/BioProtoc.2691.

Please login to post your questions/comments. Your questions will be directed to the authors of the protocol. The authors will be requested to answer your questions at their earliest convenience. Once your questions are answered, you will be informed using the email address that you register with bio-protocol.
You are highly recommended to post your data including images for the troubleshooting.

You are highly recommended to post your data (images or even videos) for the troubleshooting. For uploading videos, you may need a Google account because Bio-protocol uses YouTube to host videos.