ISSN:
1420-9071
Keywords:
Cyanogenesis
;
β-glucosidase
;
Lepidoptera
;
linamarin
;
linamarase
;
lotaustralin
;
repellent
;
Zygaenidae
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary A β-glucosidase (linamarase) was purified 52-fold with a recovery of 27% from the haemolymph of the larvae ofZygaena trifolii, ESPER, 1783 (Lepidoptera, Zygaenidae). The final enzyme preparation was found to be nearly homogeneous on both disc polyacrylamide gel electrophoresis and SDS-polyacrylamide gel electrophoresis. The molecular weight of the enzyme was determined to be about 130 kDa; it consisted of two subunits of about 66 kDa. The enzyme showed an optimum between pH 4.5 and 5 with linamarin and a broad optimum between pH 3.5 and 6.5 for p-nitrophenyl-β-D-glucoside; the temperature optimum was 40°C. The β-glucosidase showed a high specificity for its endogenous substrates linamarin and lotaustralin. Among the other natural and artificial substrates tested, only prunasin and p-nitrophenyl-β-D-glucoside were hydrolyzed by the enzyme, whereas linustatin, salicin, cellobiose and trehalose were not. The enzyme is strongly inhibited by β-glucosylpiperidine.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01974565
