Simple method for a cell count of the colonial Cyanobacterium, Microcystis sp.
The cell counting of colonial Microcystis spp. is a rather difficult and error-prone proposition, as this genus forms irregularly-shaped and irregularly-sized colonies, which are packed with cells. Thus, in order to facilitate a cell count, four methods of dividing the colonies into single cells were compared, including vortexing, sonication, TiO2 treatment, and boiling. As a result, the boiling method was determined to generate the greatest number of single cells from a colony, and all colonies were found to have divided completely after only 6 min of treatment. Furthermore, no significant cell destruction, which might alter the actual cell density, was detected in conjunction with the boiling method (P = 0.158). In order to compute the cell number more simply, the relationship between the colony size and the cell number was determined, via the boiling method. The colony volume, rather than the area or diameter was correlated more closely with the cell number (r2 = 0.727), thereby suggesting that the cell numbers of colonial Microcystis sp. can also be estimated effectively from their volumes.
Joung
Seung-Hyun
SH
Environmental Biotechnology Research Center, KRIBB, Daejeon 305-806, Republic of Korea.
Kim
Choong-Jae
CJ
Ahn
Chi-Yong
CY
Jang
Kam-Yong
KY
Boo
Sung Min
SM
Oh
Hee-Mock
HM
D000465:Algorithms; D015169:Colony Count, Microbial / Q000379:methods*; D046931:Microcystis / Q000166:cytology*; D013045:Species Specificity; D013696:Temperature