SPECTROPHOTOMETRIC ASSAY CURVES AS ANOMALOUS INDICATORS OF PROTEOLYSIS OF OILSEED PROTEINS
ROBERT L. ORY
Southern Regional Research Center Agricultural Research Service U S. Department of Agriculture New Orleans, Louisiana 701 79
One of the facilities of the Southern Region, Agricultural Research Service, U. S. Department of Agriculture Agricultural Research Service U. S. Department of Agriculture New Orleans, Louisiana 70179
Search for more papers by this authorANTONIO A. SEKUL
Southern Regional Research Center Agricultural Research Service U S. Department of Agriculture New Orleans, Louisiana 701 79
One of the facilities of the Southern Region, Agricultural Research Service, U. S. Department of Agriculture Agricultural Research Service U. S. Department of Agriculture New Orleans, Louisiana 70179
Search for more papers by this authorROBERT L. ORY
Southern Regional Research Center Agricultural Research Service U S. Department of Agriculture New Orleans, Louisiana 701 79
One of the facilities of the Southern Region, Agricultural Research Service, U. S. Department of Agriculture Agricultural Research Service U. S. Department of Agriculture New Orleans, Louisiana 70179
Search for more papers by this authorANTONIO A. SEKUL
Southern Regional Research Center Agricultural Research Service U S. Department of Agriculture New Orleans, Louisiana 701 79
One of the facilities of the Southern Region, Agricultural Research Service, U. S. Department of Agriculture Agricultural Research Service U. S. Department of Agriculture New Orleans, Louisiana 70179
Search for more papers by this authorAbstract
The methods of Anson (1938) and Lowry et al. (1951) were used to measure proteolysis of peanut proteins with and without papain. Spectrophotometric and colorimetric measurements of optical density for continuous assay of proteolysis in reaction mixtures yielded apparent hydrolysis curves, even in reactions that did not contain an added protease. Acceptance of these values as the sole criterion for proteolysis could lead to anomalous interpretations of results. The combined use of the above methods with disc gel electrophoresis gives a more accurate analysis of protein degradation by proteolysis.
REFERENCES
- Anson, M. L. 1938. The estimation of pepsin, trpsin, papain, and cathepsin with hemoglobin. J. Gen. Physiol. 22, 79–89.
- Catsimpoolas, N., Berg, T. and Meyer, E. W. 1971. Hydrogen ion titration of ionizable side-chains in native and denatured blycinin. Intern. J. Protein Res. 3, 63–71.
- Catsimpoolas, N., Campbell, T. G. and Meyer, E. W. 1969. Association-dissociation phenomena in glycinin. Arch. Biochem. Biophys. 131, 577–586.
- Catsimpoolas, N., Wang, J. and Berg, T. 1970. Spectroscopic studies on the conformation of native and denatured glycinin. Intern. J. Protein Res. 2, 277–283.
- Cherry, J. P., Mayne, R. Y. and ORY, R. L. 1974. Proteins and enzymes from seeds of Arachis hypogea L. ix. Electrophoretically detected changes in 15 peanut cultivars grown in different areas after inoculation with Aspergillus parasiticus. Physiol. Plant Pathol. 4, 425–434.
- Davis, B. J. 1964. Part II. Clinical Applications. Disc Electrophoresis-II. Method and application to human serum proteins. Ann. N. Y. Acad. Sci. 121, 404–427.
- Geiger, P. J. and Bessman, H. 1972. Protein detemination by Lowry's method in the presence of sulhydryl reagents. Anal. Biochem. 49, 467–473.
- Gerhardt, B. and Beevers, H. 1968. Influence of sucrose on protein determination by the Lowry procedure. Anal. Biochem. 24, 337–339.
- Gregory, J. D. and Sajdera, S. W. 1970. Interference in the Lowry method for protein determination. Science 169, 97–98.
- Hinton, R. H., Burge, M. L. E. and Hartman, G. C. 1969. Sucrose interference in the assay of enzymes and protein. Anal. Biochem. 29, 248–256.
- Kosower, E. M. 1964. Decreased tyrosine hydroxyl acidity through polyalanylation. Proc. Nat. Acad. Sci. 51, 1141–1146.
-
Layne, E.
1957. (73) Spectrophotometric and turbidimetric methods for measuring proteins. In
Methods in Enzymology, Vol. iii, ( S. P. Colowick and
N. O. Kaplan, eds.) p.
447, Academic Press,
New York
.
10.1016/S0076-6879(57)03413-8 Google Scholar
- Lo, C. H. and Stelson, H. 1972. Interference by polysucrose in protein determination by the Lowry method. Anal. Biochem. 45, 331–336.
- Lowry, O. H. and Lopez, J. A. 1946. The determination of inorganic phosphate in the presence of labile phosphate esters. J. Biol. Chem. 162, 421–428.
- Lowry, O. H., Rosenbrough, N. J., Farr, A. L. and Randall, R. J. 1951. Protein measurement with the Folin phenol reagent. J. Biol. Chem. 193, 265–275.
- Puri, B. R. and Bala, N. 1975. Physico-chemical properties of vegetable proteins: Part I-Electrometric titration curves. Indian J. Chem. 13, 144–148.
- Sekul, A. A. and Ory, R. L. 1977. Rapid enzymatic method for partial hydrolysis of oilseed proteins for food uses. J. Amer. Oil Chemists Soc. 54, 32–35.
- Srikanta, S. and Narasinga Rao, M. S. 1974. Effect of wet heating on the physicochemical properties of groundnut proteins. J. Agr. Food Chem. 22, 667–671.
- Wolf, W. J., Rackis, J. J., Smith, A. K., Sasame, H. A. and Babcock, G. E. 1958. Behavior of the 11 S protein of soybeans in acid solutions. I. Effects of pH, ionic strength and time on ultracentrifugal and optical rotatory properties. J. Amer. Chem. Soc. 80, 5730–5735.
