The Search for the `adaptive enzymes' sucrose phosphorylase in sucrose utilizing bacteria
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Date
1980
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Publisher
University of Colombo: UC(MED).
Abstract
Leuconostoc species from coconut toddy and from cabbage and a Klebsiella species were grown in sucrose-phosphate medium. Klebsiella species had the fastest growth rate and reached the late log phase in 9 - 10 hours while the Leuconostoc sp. from cabbage took 12 - 14 hours and that from toddy 2 and half - 3 days. They all used sucrose as the sole carbon source with the help of the enzyme invertase and not sucrose phosphorylase. The invertase from all three species were found in the 13,000g supernatant and they were not membrane bound. The activity of invertase in the Leuconostoc species (toddy) Klebsiella sp. and Leuconostoc sp. (cabbage) were 8.06, 45.0 and 77.7 units per mg protein respectively. The invertase activity was lost when the crude enzyme preparation was stored at 00C in half saturated neutral ammonium sulphate solution for 2 to 3 days. The invertase appears to be a metallo anzyme and it is 85 percent inhibited by 5 X 10 -2 M EDTA in Klebsiella and 67 percent inhibited in the sp. of Leuconostoc from cabbage. The presence of sucrose phosphorylase could not be demonstrated in all three species of bacteria by any one of the standard assay methods used. Removal of invertase by ammonium sulphate precipitation or the inhibition of invertases and phosphatases (both acid and alkaline) by the addition of sodium fluoride, tartarate, formaldehyde and EDTA also indicated the absence of sucrose phosphorylase in these bacterial species.
Description
Dissertation: M.Sc., University of Colombo: UC(MED), 1980.
Keywords
Enzymes
Citation
KANNANGARA, PN, The Search for the `adaptive enzymes' sucrose phosphorylase in sucrose utilizing bacteria, University of Colombo UC(MED), 1980: 101p.