African Journal of Biotechnology Vol. 4 (5), pp. 389-399, May 2005          
ISSN 1684–5315 © 2005 Academic Journals

Full Length Research Paper

Assessment of the genetic diversity of geographical unrelated Microcystis aeruginosa strains using amplified fragment length polymorphisms (AFLPs)

PJ Oberholster¹, A-M Botha^{2, 3}*, K Muller² and TE Cloete¹

¹Department of Microbiology and Plant Pathology, ²Department of Genetics, University of Pretoria, Hillcrest, Pretoria, ZA0002, South Africa.

³Department of Soil and Crop Sciences, Colorado State University, Fort Collins, CO80521, USA.

*Corresponding author. E-mail: AMBothaO@postino.up.ac.za or Annamaria.oberholster@FABI.up.ac.za. Tel:+27124203945. Fax: +27124203947.

Accepted 5 May, 2005

Molecular marker analysis is becoming increasingly capable of identifying informative genetic variation. Amplified fragment length polymorphism markers (AFLPs) are among the recent innovations in genetic marker technologies, and provide a greater capacity for genome coverage and more reproducible results than previous technologies. We have investigated the usefulness of AFLP, which is based on the selective amplification of genomic restriction fragments by PCR, to differentiate between geographical unrelated Microcystis strains. In total 23 strains were subjected to the AFLP fingerprinting. After analysis of the data on the basis of the average linkage method, known as the Unweighted Pair Group Method using Arithmetic averages (UPGMA), a dendrogram with four clusters was obtained. Cluster 1 consisted mainly of the NIES strains that originated from Japan, while in cluster 2 the European strains grouped together. The South African strains that originated from the northern part of the country group together in cluster 3, while the strains collected from the central and southern regions group together with the US strains in cluster 4. The study had reveals extensive evidence for the applicability of AFLP in cyanobacterial taxonomy, and furthermore clearly demonstrates the superior discriminative power of AFLP towards the differentiation of geographical unrelated Microcystis aeruginosa strains that belong to the same species, as well as highlighting the potential of this fingerprinting method in evolutionary studies.  

Key words: Molecular markers, Distribution, Cyanobacteria, Genetic diversity.