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  • Proteases and nucleases involved in the biphasic digestion process of the brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae)
Title: Proteases and nucleases involved in the biphasic digestion process of the brown marmorated stink bug, Halyomorpha halys (Hemiptera: Pentatomidae)
Abstract

Management of the brown marmorated stink bug,Halyomorpha halys(Hemiptera: Pentatomidae), an invasive, agricultural pest in the United States, has presented significant challenges. This polyphagous insect uses both extra‐oral and gut‐based digestion thwarting protein‐ or nucleotide‐based control strategies. The objective of this study was to biochemically characterize the digestive enzymes (proteases and nucleases) from the saliva, salivary gland and the gut ofH. halys. Enzyme profiles for the two tissues and saliva radically differ: The pH optimum for proteases in the gut was six, with cysteine proteases predominant. In contrast, the alkaline pH optima for protease activity in the salivary gland (8–10) and saliva (7) reflected abundant serine protease and cathepsin activities. RNase enzymes were most abundant in saliva, while dsRNase and DNase activities were higher in the salivary gland and saliva compared to those in the gut. These very different enzyme profiles highlight the biphasic digestive system used by this invasive species for efficient processing of plant nutrients. Knowledge ofH. halysdigestive physiology will allow for counteractive measures targeting digestive enzymes or for appropriate protection of protein‐ or nucleotide‐based management options targeting this pest.

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Award ID(s):
1338775 1821914
NSF-PAR ID:
10054539
Author(s) / Creator(s):
 ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Archives of Insect Biochemistry and Physiology
Volume:
98
Issue:
3
ISSN:
0739-4462
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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