@article { ISI:000230613600002, title = {Unraveling biochemical properties of cockroach (Periplaneta americana) proteinases with a gel X-ray film contact print method}, journal = {Comparative Biochemistry and Physiology B-Biochemistry \& Molecular Biology}, volume = {141}, number = {3}, year = {2005}, month = {JUL}, pages = {261-266}, publisher = {ELSEVIER SCIENCE INC}, type = {Article}, address = {360 PARK AVE SOUTH, NEW YORK, NY 10010-1710 USA}, abstract = {

Eleven proteinase activity bands were detected in American cockroach (Periplaneta americana) gut. These were partially purified and characterized using a gel X-ray film contact print method. Cockroach gut proteinases (CGPs) show activity over a broad range of pH with maximum activity between pH 6 and 10, and optimal activity at 50-70 degrees C. CGPs were partially purified by preparative gel electrophoresis and analyzed using synthetic substrates and inhibitors. Four of the proteases exhibited chymotrypsin-like (C1 to C4) activity and seven trypsin-like (T I to T7) activity. Accuracy of the gel X-ray film contact print method is confirmed by including bovine chymotrypsin in CGP analysis. Inhibition of CGPs with different plant proteinaceous proteinase inhibitors allowed identification of potential CGP inhibitors. Our results imply that presence of several CGP activity bands, and their stability and activity over a broad pH and temperature range might contribute to adaptation of P americana to extreme environmental conditions and the polyphagous nature of the species. (c) 2005 Elsevier Inc. All rights reserved.

}, keywords = {activity visualization, cockroach, gut enzymes, Periplaneta americana, plant proteinase inhibitors, Proteinases}, issn = {1096-4959}, doi = {10.1016/cbpc.2005.02.015}, author = {Hivrale, Vandana K. and Chougule, Nanasaheb P. and Chhabda, Pavan J. and Giri, Ashok P. and Kachole, M. S.} } @article { ISI:000291879600008, title = {Biochemical characterisation of alpha-amylase inhibitors from achyranthes aspera and their interactions with digestive amylases of coleopteran and lepidopteran insects}, journal = {Journal of the Science of Food and Agriculture}, volume = {91}, number = {10}, year = {2011}, month = {AUG}, pages = {1773-1780}, publisher = {WILEY-BLACKWELL}, address = {111 RIVER ST, HOBOKEN 07030-5774, NJ USA}, abstract = {

BACKGROUND: Starchy seeds are an important food and a source of dietary ingredients in many countries. However, they suffer from extensive predation by bruchids (weevils) and other pests. alpha-Amylase inhibitors are attractive candidates for the control of seed weevils, as these insects are highly dependent on starch as an energy source. RESULTS: A proteinaceous alpha-amylase inhibitor from the seeds of Achyranthes aspera was identified, purified and characterised. In electrophoretic analysis, two prominent amylase inhibitor activity bands (AI1 and AI2) were detected. The inhibitor was purified 9.99-fold with 1206.95 total amylase inhibitor units mg(-1) protein. The molecular weight of the purified inhibitor was around 6 kDa. The isolated alpha-amylase inhibitor was found to be resistant to heat and proteolysis. Feeding analysis of Callosobruchus maculatus larvae on a diet containing seed powder of A. aspera revealed that survival of the larvae was severely affected, with the highest mortality rate occurring on the fifth day of feeding. The isolated inhibitor inhibited the majority of amylase isoforms of C. maculatus, Tribolium confusum and Helicoverpa armigera in electrophoretic analysis and solution assays. CONCLUSION: The information obtained in the present investigation could be useful for a genetic engineering approach that would make seeds resistant to storage pest infestations. (C) 2011 Society of Chemical Industry

}, keywords = {Achyranthes aspera, Amylase inhibitors, amylases, Callosobruchus maculatus, Tribolium confusum}, issn = {0022-5142}, doi = {10.1002/jsfa.4380}, author = {Hivrale, Vandana K. and Chougule, Nanasaheb P. and Giri, Ashok P. and Chhabda, Pavan J. and Kachole, Andmanvendra S.} } @article { ISI:000325423500046, title = {Alterations in the helicoverpa armigera midgut digestive physiology after ingestion of pigeon pea inducible leucine aminopeptidase}, journal = {Plos One}, volume = {8}, number = {9}, year = {2013}, month = {SEP}, pages = {e74889}, publisher = {PUBLIC LIBRARY SCIENCE}, address = {1160 BATTERY STREET, STE 100, SAN FRANCISCO, CA 94111 USA}, abstract = {

Jasmonate inducible plant leucine aminopeptidase (LAP) is proposed to serve as direct defense in the insect midgut. However, exact functions of inducible plant LAPs in the insect midgut remain to be estimated. In the present investigation, we report the direct defensive role of pigeon pea inducible LAP in the midgut of Helicoverpa armigera (Lepidoptera: Noctuidae) and responses of midgut soluble aminopeptidases and serine proteinases upon LAP ingestion. Larval growth and survival was significantly reduced on the diets supplemented with pigeon pea LAP. Aminopeptidase activities in larvae remain unaltered in presence or absence of inducible LAP in the diet. On the contrary, serine proteinase activities were significantly decreased in the larvae reared on pigeon pea LAP containing diet as compared to larvae fed on diet without LAP. Our data suggest that pigeon pea inducible LAP is responsible for the degradation of midgut serine proteinases upon ingestion. Reduction in the aminopeptidase activity with LpNA in the H. armigera larvae was compensated with an induction of aminopeptidase activity with ApNA. Our findings could be helpful to further dissect the roles of plant inducible LAPs in the direct plant defense against herbivory.

}, issn = {1932-6203}, doi = {10.1371/journal.pone.0074889}, author = {Lomate, Purushottam R. and Jadhav, Bhakti R. and Giri, Ashok P. and Hivrale, Vandana K.} } @article { ISI:000328395400001, title = {Characterization of a chemostable serine alkaline protease from Periplaneta americana}, journal = {BMC Biochemistry}, volume = {14}, year = {2013}, month = {NOV}, pages = {32}, publisher = {BIOMED CENTRAL LTD}, address = {236 GRAYS INN RD, FLOOR 6, LONDON WC1X 8HL, ENGLAND}, abstract = {

Background: Proteases are important enzymes involved in numerous essential physiological processes and hold a strong potential for industrial applications. The proteolytic activity of insects{\textquoteright} gut is endowed by many isoforms with diverse properties and specificities. Thus, insect proteases can act as a tool in industrial processes. Results: In the present study, purification and properties of a serine alkaline protease from Periplaneta americana and its potential application as an additive in various bio-formulations are reported. The enzyme was purified near to homogeneity by using acetone precipitation and Sephadex G-100 gel filtration chromatography. Enzyme activity was increased up to 4.2 fold after gel filtration chromatography. The purified enzyme appeared as single protein-band with a molecular mass of similar to 27.8 kDa in SDS-PAGE. The optimum pH and temperature for the proteolytic activity for purified protein were found around pH 8.0 and 60 degrees C respectively. Complete inhibition of the purified enzyme by phenylmethylsulfonyl fluoride confirmed that the protease was of serine-type. The purified enzyme revealed high stability and compatibility towards detergents, oxidizing, reducing, and bleaching agents. In addition, enzyme also showed stability towards organic solvents and commercial detergents. Conclusion: Several important properties of a serine protease from P. Americana were revealed. Moreover, insects can serve as excellent and alternative source of industrially important proteases with unique properties, which can be utilized as additives in detergents, stain removers and other bio-formulations. Properties of the P. americana protease accounted in the present investigation can be exploited further in various industrial processes. As an industrial prospective, identification of enzymes with varying essential properties from different insect species might be good approach and bioresource.

}, keywords = {Chemostability, Industrial catalyst, Insect proteases, Periplaneta americana, Serine alkaline protease}, issn = {1471-2091}, doi = {10.1186/1471-2091-14-32}, author = {Sanatan, Prashant T. and Lomate, Purushottam R. and Giri, Ashok P. and Hivrale, Vandana K.} } @article { ISI:000319229900002, title = {Compensatory proteolytic responses to dietary proteinase inhibitors from Albizia lebbeck seeds in the helicoverpa armigera larvae}, journal = {Arthropod-Plant Interactions}, volume = {7}, number = {3}, year = {2013}, month = {JUN}, pages = {259-266}, publisher = {SPRINGER}, address = {VAN GODEWIJCKSTRAAT 30, 3311 GZ DORDRECHT, NETHERLANDS}, abstract = {

Plant proteinase inhibitors (PIs) have been shown to reduce the growth rates in larvae of numerous insect species. On the other hand, insects can also regulate their proteinases against plant PIs. In the present study, we report the compensatory activities of Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) gut proteinases against the PIs of Albizia lebbeck seeds. Total of ten proteinase inhibitor bands were detected in the seed extract of A. lebbeck. Bioassays were conducted by feeding H. armigera larvae on diet containing partially purified PIs from A. lebbeck seeds. Results show that larval growth and survival was significantly reduced by A. lebbeck PIs. We found that higher activity H. armigera gut proteinase (HGP) isoforms observed in the midgut of control larvae were inhibited in the midgut of larvae fed on test diet. Some HGP isoforms were induced in the larvae fed on PI containing test diet; however, these isoforms showed lower activity in the larvae fed on control diet. Aminopeptidase activities were significantly increased in the midgut of larvae fed on test diet. A population of susceptible and resistant enzymes was observed in the midgut of H. armigera, when fed on diet containing PIs from A. lebbeck seeds. Our initial observations indicate that H. armigera can regulate its digestive proteinase activity against non-host plant PIs, too. It is important to study the exact biochemical and molecular mechanisms underlying this phenomenon in order to develop PI-based insect control strategies.

}, keywords = {Albizia lebbeck, Helicoverpa armigera, Midgut proteinases, Proteinase inhibitors, regulation}, issn = {1872-8855}, doi = {10.1007/s11829-012-9240-1}, author = {Hivrale, Vandana K. and Lomate, Purushottam R. and Basaiyye, Shriniwas S. and Kalve, Neeta D.} }