Multilocus enzyme electrophoresis methods for the analysis of bacterial population genetic structure

This chapter provides specific information on multilocus enzyme electrophoresis (MLEE) techniques that have proven to be especially useful in the study of Rhizobium and other soil bacteria. The genes examined in MLEE analyses are usually "housekeeping" enzyme genes, or genes that occur in basic metabolic pathways. In addition to providing information on genetic relatedness and genetic diversity in natural bacterial populations, MLEE data are useful in assessing the importance of previous chromosomal recombination in a population. These analyses are based on the premise that, when blocks of genes recombine repeatedly in a population, alleles at different enzyme loci eventually become randomized. Genetic diversity estimates can be calculated for populations and individual loci using MLEE allele frequency data. There are numerous examples of population genetic studies in the literature that may serve as useful references for interpreting MLEE data. Publication-quality dendograms illustrating relationships between strains can be drawn with a variety of computer programs.