Identification and characterization of hydrolytic enzymes from the midgut of Sunn Pest of wheat (Eurygaster integriceps)


Ogur E., YÜCEL M., ÖKTEM H. A.

INTERNATIONAL JOURNAL OF PEST MANAGEMENT, cilt.55, ss.359-364, 2009 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 55 Konu: 4
  • Basım Tarihi: 2009
  • Doi Numarası: 10.1080/09670870902939897
  • Dergi Adı: INTERNATIONAL JOURNAL OF PEST MANAGEMENT
  • Sayfa Sayıları: ss.359-364

Özet

To help in the development of Sunn Pest-resistant transgenic plants employing protease or alpha-amylase inhibitors, midgut hydrolytic enzymes of Sunn Pest (Eurygaster integriceps, Put.) (Heteroptera: Scutelleridae) were identified and characterized biochemically. We observed levels of very low proteolytic activity of trypsin (3 nmoles/min/mg), elastase (0.66 nmoles/min/mg) and leucine aminopeptidase-like (14.4 nmoles/min/mg) proteases, but no chymotrypsin and papain-like activity. Proteolytic activities were insensitive to inhibition by soybean trypsin inhibitor (SBTI) and aprotinin, but were inhibited to varying degrees (40-100%) by the synthetic protease inhibitors PMSF, TPCK, CdCl2 and CuCl2. Compared to proteolytic activity, significantly higher amylolytic activity (4.45 mmoles/min/mg) was observed. Alpha-amylase activity was found to be resistant to inhibition by bean and chickpea alpha-amylase inhibitors, and only slightly inhibited by wheat (36.9 +/- 1.8%) and maize (40.2 +/- 2.8) alpha-amylase inhibitors. Here, we report on the biochemical properties of digestive enzymes from Sunn Pest midgut, and their inhibition patterns by several synthetic and natural hydrolytic enzyme inhibitors.