Seminars & Events

"Coenzyme-Q biosynthesis: A novel pathway for p-hydroxybenzoate in klebsiella oxytoca"

DATE: October 5, 2011
TIME: 1:00 PM - 2:00 PM
SPEAKER: Janaka Edirisinghe, NIU Dept. of Biological Sciences Graduate Student
LOCATION: TCS Building 240, Room 4301, Argonne National Laboratory

Description:
Seminar: Coenzyme-Q (Q; ubiquinone) is widely distributed in living organisms and is a component of the mitochondrial respiratory chain. It was thought that in eukaryotes it is present only in the respiratory chain; however, recent developments have shown that it is distributed in all cell membranes. It undergoes oxidation-reduction in cell membranes of lysosomes, golgi and functions as an antioxidant, either by direct reaction with free radicals or by regeneration of vitamins E and C. Prokaryotes such as Escherichia coli synthesize p-hydroxybenzoate (PHB), the precursor of Q, directly from the shikimate pathway via chorismate. Higher animals including humans lack the shikimate pathway and hence synthesize PHB from the essential amino acid tyrosine. However, the steps involved in the formation of PHB from tyrosine are not known. In this study, we show that Klebsiella oxytoca, can synthesize PHB from chorismate similar to E.coli as well as from tyrosine similar to humans. We propose an alternate pathway for the conversion of tyrosine to PHB and provide supporting evidence.

Save the event to your calendar [schedule.ics]