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Calvin
Tormanen (Professor)
Ph.D., University of
Minnesota
B.S. University of
Minnesota
Office:
Dow 347
Phone:
(989) 774 - 3252
Fax:
(989) 774 - 3883
E-mail:
torma1cd@mail.cmich.edu
Additional
Information at: Dr.
Tormanen's Home Page
Teaching Emphasis:
Biochemistry lecture
and laboratory courses (CHM 421, 425, 521, 522, 527, and 680)
General Chemistry
lecture and laboratory courses (CHM 120, 127, 131, and 132)
Research Program and
Goals:
Dr.
Tormanen's research involves the investigation of the structure and properties
of the enzymes arginase and glycine transamidinase. Arginase catalyzes the
hydrolysis of arginine to form urea and ornithine. Glycine transamidinase
catalyzes the transfer of the amidine group from arginine to glycine to form
guanidinoacetate and ornithine. Animals produce urea to remove excess nitrogen
from the body. Vertebrates produce creatine from guanidinoacetate. Creatine
phosphate serves as the shuttle for high energy phosphate produced in the
mitochondria and utilized in the cytosol. Creatine phosphate phosphorylates ADP
producing ATP which is used to provide the energy for muscular contraction and
active transport of ions.
Glycine transamidinase has been purified from the
mitochondrial and cytosolic fractions of rat kidney homogenate (5). The
properties of the isozymes such as molecular weight, electrophoretic mobility,
and activation energy have been determined. Purified transamidinase has been
stabilized with the addition of polyethylene glycol (6).
The effect of metal ions on arginase activity in the
zebra mussel has been studied (7). The zebra mussel is a clam that has recently
invaded the Great Lakes from Europe. It is having a serious economic impact
because it plugs the raw-water systems of utilities. Zebra mussel arginase
requires manganese, nickel, or cobalt for activity. Other metal ions inhibit the
enzyme.
The inhibition of rat liver and kidney arginase by
copper and mercury ions has been studied (8). Mercury ions are heavy metal
poison found in natural waters. Although copper is required as a cofactor by
some enzymes, it is harmful in larger amounts.
The inhibition of rat liver and kidney arginase by
fluoride has been studied most recently (9). Although fluoride is a well-known
enzyme poison, it is added to drinking water and toothpaste.
Students have the
opportunity to work with both native and laboratory animals. Some of the
biochemistry laboratory techniques that are used include enzyme assays,
differential centrifugation, solubilization of mitochondrial enzymes,
purification of enzymes using column chromatography, and separation of enzymes
by polyacrylamide gel electrophoresis.
Selected
Publications:
Tormanen,
C.D., “Allosteric inhibition of rat liver and kidney arginase by copper and
mercury ions”, Journal of Enzyme Inhibition 16, 443-449, 2001.
Tormanen, C.D.,
"Substrate inhibition of rat liver and kidney arginase with fluoride",
Journal of Inorganic Biochemistry, volume 93, pages 243-246, 2003.
"Comparison
of the inhibition of rat liver and kidney arginase by metal ions", paper
presented at the International Union of Biochemistry Congress in Birmingham,
England, July 2000.
"The effect of metal ions on arginase from the zebra mussel Dreissena
polymorpha", Journal of Inorganic Biochemistry 66, 111-118 (1997).
"The effect of pH on the inhibition of rat liver arginase by fluoride,
chloride, and bromide", paper presented at the Midwest Enzyme Conference in
Chicago, Illinois, October 1997
"Cryoprotection of purified rat kidney transamidinase by polyethylene
glycol", Cryobiology 29, 511-518 (l992).
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