Purification of an Enzyme from Yeast Which Liberates Protein-bound Thioctic Acid

Removal of thioctic acid from enzymes.

The r81e of thioctic acid in t’he oxidative decarboxylation of or-keto acids is now well established (1, 2). This was accomplished largely by studies with microbial cells grown essentially free of the cofactor. In some instances (2) it has been possible t,o separate the coenzyme from microbial enzymes involved in t,hioctic acid metabolism by extensive purification procedures. Although tjhe dire...

Purification and properties of an enzyme from beef liver which catalyzes sulfhydryl-disulfide interchange in proteins.

An enzyme which catalyzes sulfhydryl-disulfide interchange in proteins containing “incorrect” disulfide bonds has been isolated from beef liver microsomes. The purified form of this enzyme shows two bands upon electrophoresis in starch gels and polyacrylamide gels. The proteins represented by these bands are considered to be variants of the same protein because both are enzymically active after...

Protein purification from whole tissues . Fatemeh Mehrpooyan*

Staphylococcal acid phosphatase: extensive purification and characterization of the loosely bound enzyme.

Acid phosphatase of Staphylococcus aureus PS55 was eluted from the surface of these cells with 1.0 m KCl at pH 8.5 by gentle agitation at 25 C and was purified 44-fold (51% recovery) by two cycles of dialysis and gel filtration. The eluted enzyme which had a 280/260 (nm) absorbancy ratio of 0.71 required at least 0.5 m salt solution for solubilization; however, most of the purified product whic...

Purification and characterization of antiviral protein from silkworm fecal matter

Antiviral proteins (AVP), present in silkworm fecal matter, show activity against nuclear polyhedrosis virus (NPV) in vitro and in vivo. The extract of silkworm fecal matter prepared in phosphate buffer solution of pH 7.5 was subjected to 50% solid ammonium sulfate precipitation to enrich AVP, then which was dialyzed. The dialysate was applied to the column containing silica gel-G, the column e...