A stopped-flow mixer device for a batch microcalorimeter application to NAD-NADase reaction.
A new molded polypropylene, diamond-like carbon (DLC)-coated mixing cell has been developed for use in the batch microcalorimeter. Reagent volume can be varied from 25 microliters to 100 microliters. A 10 microcalorie reaction heat can be measured to 5%. Repeat reactions can be done as often as every 10 min for a fast reaction. Reactions can be started within 1 h or less after loading. A pre-equilibrator and a temperature-controlled syringe drive unit permit solutions to be stored at 4 degrees C while being run at any temperature from -20 degrees C to 40 degrees C. The kinetics and enthalpy of reaction of NAD-NADase have been measured. delta H is about 21 kcal/mol endothermic.
Berger
R L
RL
National Heart, Lung, and Blood Institute, Laboratory of Technical Development, Bethesda, MD 20892.
Mudd
C P
CP
Clem
T
T
Kolobow
T
T
Beile
E
E
Simons
P C
PC
Michel
S
S
McClintock
W
W
D002151:Calorimetry / Q000295:instrumentation / Q000379:methods; D007700:Kinetics; D008832:Microchemistry; D009243:NAD / Q000378:metabolism*; D009244:NAD+ Nucleosidase / Q000378:metabolism*
D009243:NAD; D009244:NAD+ Nucleosidase