Resolution of six chromosomes of Trichomonas vaginalis and conservation of size and number among isolates

Abstract

The electrophoretic karyotype of Trichomonas vaginalis isolates was determined by contour-clamped homogeneous electric field electrophoresis. Six chromosomal bands ranging between 50 kbp and 6 Mbp were reliably resolved by our separation method. Trichomonad chromosomes fell into 3 distinct size classes. The 3 maxichromosomes were approximately 5,700, 4,700, and 3,500 kbp. Two intermediate-sized chromosomes were ~1,200 kbp and 1,100 kbp. A minichromosome was ~75 kbp. The same size and number of chromosomes were present in 15 T. vaginalis isolates obtained from different geographic regions, reinforcing the idea of a highly conserved karyotype among trichomonal isolates worldwide.