Purification and properties of an extracellular esterase from a cold-adapted Pseudomonas mandelii.
An extracellular esterase, EstK, was purified from the psychrotrophic bacterium Pseudomonas mandelii grown at 25°C. Prior to harvest, cells were treated with 0.2 M MgCl2 to precipitate lipopolysaccharides in the outer membranes, which otherwise form aggregates with the secreted enzymes. EstK was purified to homogeneity using standard procedures. It had substrate specificity towards esters of short-chain fatty acids, particularly, p-nitrophenyl acetate. Optimum activity of EstK was at 40°C; at 4°C the activity was ~50% of its maximum. EstK has a unique substrate preference for p-nitrophenyl acetate and remains active at low temperatures.
Department of Biomedical Science, Daegu University, Gyeongsan, Korea. cookie9hee@nate.com
Seunghee
S
Hong
ChangWoo
C
Lee
Sei-Heon
SH
Jang
D003080:Cold Temperature; D004795:Enzyme Stability; D004950:Esterases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D011549:Pseudomonas / Q000201:enzymology* / Q000502:physiology; D013379:Substrate Specificity; D013696:Temperature
D005227:Fatty Acids; D004950:Esterases