The molecular diversity of the purple photosynthetic bacteria was assessed during temporal pigmentation changes in four interconnected wastewater stabilization ponds treating domestic wastewater by denaturant gel gradient electrophoresis method applying p
ufM gene. Results revealed high phylogenetic diversity of the purple phototrophic anoxygenic bacteria community characterized by the presence of the purple non-sulfur, purple sulfur, and purple aerobic photosynthetic anoxygenic bacteria. This phototrophic bacterial assemblage was dominated by the purple non-sulfur bacteria group (59.3 %) with six different genera followed by the purple sulfur community (27.8 %) with four genera and finally 12.9 % of the p
ufM gene sequences were assigned throughout the aerobic anoxygenic phototrophic bacterial group. The purple phototrophic bacterial community was characterized by the presence of salt-dependant bacterial species belonging to the genus
Marichromatium
,
Thiorhodococcus
,
Erythrobacter
, and
Roseobacter
. The wastewater treatment plant performances were unsatisfactory, and the biological and chemical parameters suggested that the purple photosynthetic bloom was correlated with the eutrophic state.
