Chromatography isozymes

A comparison of spontaneously and experimentally released -lactamase preparations of B. licheniformis (40) indicates that the ends of the polypeptide chain can vary without affecting the properties of the enzyme. Although such preparations differ in the C- and N-terminus, they are serologically and catalytically indistinguishable (40,63). Similarly, B. licheniformis 749/C isozymes, separable by starch gel electrophoresis or DEAE-chromatography and believed to differ at the C- or N-terminus (40), have identical substrate specificities (Table V). 

Scott (80) purified red cell acid phosphatase of homozygous types A and B by using ammonium sulfate and DEAE-cellulose chromatography. The relative activity of these isozyme preparations was the same when tested with a number of substrates. Type B enzyme showed small kinetic... 

The heritable nature of red cell acid phosphatase isozymes was discovered with the aid of the high separation power of starch gel chromatography. However, if the physical differences found in the isozymes... 

In barley, four branching enzyme isozymes were identified by separation via fast performance liquid chromatography, and three were partially purified.262... 

LiP has been purified to electrophoretic homogeneity by a combination of anion exchange chromatography and gel filtration (26-28). The enzyme is present as a series of Isozymes (28,29) with pi ranging from 3.2 to 4.0. LIP contains one mole of iron protoporphyrin IX per mole of enzyme and is a glycoprotein of molecular mass 41,000. 

A GST enzyme from pea Is very effective In catalyzing GSH conjugation of the herbicide fluorodlfen ( ). This enzyme has a pH optimum and other properties that are comparable to mammalian GST enzymes (85). This enzyme activity was observed In other plant species, but fluorodlfen resistant species appeared to have higher levels of this enzyme than susceptible species ( ). Additional studies with pea Indicated the presence of two soluble GST Isozymes, one that utilized fluorodlfen and one that utilized -cinnamic acid as substrates (W7). These Isozymes appeared to form aggregates during purification. In addition, a microsomal GST was detected In pea that utilized both -cinnamic acid and benzo(a)pyrene as substrates (WT.). Soybean cell suspension cultures metabolized -clnnamlc acid In a 6% yield to a product that corresponded to the GSH conjugate of t-clnnamlc acid by paper chromatography (107). 

L2. La Du, B. N., and Choi, Y. S., Separation of atypical and usual forms of human serum cholinesterase by affinity chromatography. In Isozymes, II. Physiological Function" (C. L. Markert, ed.), pp. 877-886. Academic Press, New York, 1975. 

Additional information <1> (<1> tissue distribution, in extrahepatic tissue only 10% or less of activity in liver [16] <1> POROS-HQ column chromatography followed by Western blot analysis of extracts from various rat tissues show that proteins of placenta-type isozyme are expressed in placenta, brain, testis, liver, spleen, heart and lung, but not in kidney and skeletal muscle [55]) [16, 55]... 

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