Brian Colman PhD (Wales) not accepting graduate students E-mail: colman@yorku.ca Research Areas: Plant Physiology, Cell Biology |
Plant physiology with special interests in photosynthesis in algae, particularly the processes of active inorganic carbon uptake and photosynthetic carbon metabolism. My students and I have been conducting studies on the biochemistry and physiology of photorespiration and inorganic carbon transport in photosynthetic plant cells.
Many higher plants, i.e. C3 plants, lose a significant fraction of their newly fixed carbon by photorespiration, which reduces net CO2 fixation by plants and is reflected in crop plants by a loss in yield. Some high yield crop species, such as corn, do not photorespire. The suppression of photorespiration in these C4 plants is achieved by a combination of complex leaf anatomy and an accessory CO2 fixation pathway which concentrates CO2 at the enzyme site of carbon fixation.
In most aquatic plants, particular unicellular algae and cyanobacteria, photorespiration is suppressed by the intracellular accumulation of inorganic carbon by active uptake of HCO3- and CO2 from the external medium. We have shown that active bicarbonate transport occurs widely in the algae: in unicellular diatoms and red algae, and in thalloid red, brown and green algae. Active CO2 transport, originally found in cyanobacteria, has also been found in several unicellular green algae and in diatoms. Current studies in the laboratory are being conducted on the function of carbonic anhydrase in inorganic carbon uptake, and of the mechanisms of CO2 and HCO3- uptake in green algae, diatoms and a number of marine microalgae.
Huertas, I.E., S. Bhatti & B. Colman. 2003. Inorganic carbon acquisition in two species of marine prymnesiophytes. European J. Phycol. 38:181-189.
Bhatti, S., I.E.Huertas & B.Colman. 2002. Acquisition of inorganic carbon by the marine haptophyte Isochrysis galbana. J. Phycology 38:914-921.
Colman, B., I.E.Huertas, S.Bhatti, & J.S.Dason. 2002. The diversity of inorganic carbon acquisition mechanisms in eukaryotic microalgae. Functional Plant Biology 29(2):261-270.
Huertas, I.E., B.Colman & G.S. Espie. 2002. Inorganic carbon acquisition and its energisation in eustigmatophycean algae. Functional Plant Biology 29(2):271-277.
Huertas, I.E., B. Colman & G.S. Espie. 2002. Mitochondrial-driven bicarbonate transport supports photosynthesis in a marine microalga. Plant Physiol. 130:284-291.
Huertas, E.I., G.S. Espie & B.Colman. 2002. The energy source for CO2 transport in the marine microalga Nannochloris atomus. Planta. 214:947-953.
Matsuda, Y., T. Hara & B.Colman. 2001. Regulation of the induction of bicarbonate uptake by dissolved CO2 in the marine alga Phaeodactylum tricornutum. Plant, Cell & Environ. 24:611-620.
Deveau, J.S.T., R.R. Lew & B.Colman. 2001. Evidence for active CO2 uptake by a CO2-ATPase in the acidophilic green alga Eremosphaera viridis. Can.J.Botany. 79:1274-1281.
