In:
European Journal of Biochemistry, Wiley, Vol. 20, No. 4 ( 1971-06), p. 459-468
Abstract:
The phospholipase A from the venom of the common European honey bee ( Apis mellifica ) has been completely purified. The final product (13 g from 700 g of crude venom) readily crystallizes and is homogeneous with respect to starch gel electrophoresis at pH 8.0, isoelectric focussing in polyacrylamide gel in the pH range 3–10, and sedimentation and diffusion analysis in the ultracentrifuge. Only one N‐terminal residue, isoleucine, can be detected either by the Edman or dansyl methods. Quantitative N‐terminal analysis and gel filtration on Sephadex G‐100 give values for the molecular weight of about 19000. Ultracentrifugation studies lead to a value of about 40000: in concentrated solution the molecule exists, therefore, as a dimer. The identity of the enzyme as a phospholipase of the A 2 type has been confirmed since, with 1‐oleyl‐2‐isolauroyl phosphatidyl ethanolamine as substrate, isolauric acid is liberated in 100% yield whereas no oleic acid is released. A method for the assay of the enzyme based on continuous titrimetric estimation of hexanoic acid liberated from 1,2‐dihexanoyl lecithin has been used to study various aspects of the activity of the enzyme.
Type of Medium:
Online Resource
ISSN:
0014-2956
,
1432-1033
DOI:
10.1111/ejb.1971.20.issue-4
DOI:
10.1111/j.1432-1033.1971.tb01414.x
Language:
English
Publisher:
Wiley
Publication Date:
1971
detail.hit.zdb_id:
1398347-7
detail.hit.zdb_id:
2172518-4
SSG:
12
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