Premium
PARTIAL PURIFICATION AND CHARACTERIZATION OF TRANSGLUTAMINASE FROM THREADFIN BREAM ( NEMIPTERUS SP.) LIVER
Author(s) -
HEMUNG BUNGORN,
YONGSAWATDIGUL JIRAWAT
Publication year - 2008
Publication title -
journal of food biochemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.507
H-Index - 47
eISSN - 1745-4514
pISSN - 0145-8884
DOI - 10.1111/j.1745-4514.2008.00154.x
Subject(s) - tissue transglutaminase , dithiothreitol , enzyme , chemistry , biochemistry , myosin , polyacrylamide gel electrophoresis , enzyme assay , gel electrophoresis , molecular mass , sodium dodecyl sulfate , size exclusion chromatography , chromatography
Transglutaminase (TGase) from the threadfin bream ([TB] Nemipterus sp.) liver was partially purified using ion exchange, size exclusion and affinity chromatography. Three protein bands with molecular weight (Mw) of 95, 63 and 43 kDa on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‐PAGE) were observed. Only one distinct fluorescent band appeared on the TGase activity staining of the native‐PAGE. When the protein band was eluted and analyzed on the SDS‐PAGE, it showed a single band with an Mw of 95 kDa. The enzyme required Ca 2 + up to 1 mM for full activation. TGase was also activated by 10 mM Sr 2 + . Dithiothreitol had no effect on activity. TGase activity was unaffected by NaCl up to 0.6 M and reduced to 75% at 1.2 M NaCl. Optimum pH and temperature was 8.5–9.0 and 50C, respectively. TGase activity was markedly inhibited by the sulfhydryl reagents. The enzyme catalyzed the cross‐linking of the TB myosin heavy chains.PRACTICAL APPLICATIONS Threadfin bream (TB) liver transglutaminase (TGase) exhibited Ca 2+ ‐dependent characteristic similar to muscle TGase. The enzyme catalyzed the cross‐linking of myosin, and therefore, could be applied to improve the textural properties of muscle proteins. The enzyme remained its high activity up to 1.2 M NaCl (≈7% w/v), indicating its potential application in foods containing a relatively high NaCl. The biochemical characteristics of the TB liver TGase are critical information leading to more understanding in the nature of the enzyme as well as determining the optimum conditions for food applications. Moreover, the presented purification scheme could be adopted to recover TGase from the TB liver, which is currently a solid waste of the surimi industry.