Aerobic Anoxygenic Phototrophs
The aerobic anoxygenic phototrophs (AAP) are a recently discovered group of bacteria that belongs mostly to the alpha-proteobacteria. However, few isolates are classified within the beta- and gamma- proteobacteria. They are photoheterotrophs unable to fix CO2. The geography of their distribution is very wide and AAP are found in practically every environment tested. AAP possess bacteriochlorophyll a associated with a membrane bound photosynthetic apparatus (PSA) similar to that of the anoxygenic phototrophic purple bacteria. The PSA consists of a reaction center bound to the light harvesting I complex with some strains containing an additional peripheral light harvesting II complex. The photosynthetic machinery is unique in that it functions only in the presence of oxygen unlike any other type of bacteria that utilize bacteriochlorophyll. Many other unanswered questions are associated with the unique phenomena of AAP. Our laboratory is trying to contribute to international efforts to solve these riddles by active research in diversity, ecology, physiology, biochemistry, and molecular biology of AAP.
Bacterial Heavy Metal Transformations
Tellurium (Te), vanadium (V), and to some extent selenium (Se), have become abundant in the environment due to industrial activity. The oxides of these elements are extremely toxic to most living organisms. However, some extremely metal tolerant bacteria demonstrate great promise in bioremediation of these toxins from ecosystems. They can reduce toxic oxides, converting them into less harmful elemental metallic states. Our laboratory investigates this process from different perspectives including environmental, physiological, biochemical, and molecular biological aspects.
