4.5 Article

Biochemical characterization of three midgut chitin deacetylases of the Lepidopteran insect Bombyx mori

Journal

JOURNAL OF INSECT PHYSIOLOGY
Volume 113, Issue -, Pages 42-48

Publisher

PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.jinsphys.2019.01.005

Keywords

Chitin deacetylase; Peritrophic membrane; Deacetylation activity; Protein expression; Functional specialization; Lepidoptera

Funding

  1. Program for National Natural Science Funds for Distinguished Young Scholar [31425021]
  2. National Natural Science Foundation of China [31772193]
  3. National Key RAMP
  4. D Program of China [2017YFD0200502]

Ask authors/readers for more resources

Peritrophic membrane (PM) is a chitin and protein-containing extracellular matrix that lines the midgut in most insect species, functioning as a barrier to exogenous toxins and pathogens. Midgut chitin deacetylases (CDAs) are chitin-modifying enzymes known to alter the mechanical property and permeability of PM. However, biochemical properties and specific roles of these enzymes remain elusive. In this study, the midgut-expressed CDAs (BmCDA6, BmCDA7 and BmCDA8) from Bombyx mori were cloned, recombinantly expressed and purified and their enzymatic activities toward PM chitin were determined. Of the three enzymes, BmCDA7 exhibited the highest activity (0.284 mu mol/min/mu mol), while BmCDA8 showed lower activity of 0.061 mu mol/min/mu mol. BmCDA6 was inactive towards PM chitin. Gene expression patterns indicated that although all three CDA genes were specifically expressed in the anterior midgut, they differed in their temporal expression patterns. BmCDA6 was expressed almost exclusively at the mid-molt stage, the stage when the PM was thick and with multiple chitin layers. Unlike BmCDA6, high expression levels of BmCDA7 and BmCDA8 were observed only at the feeding stage, the stage when the PM is thin and with fewer chitin layers. The different gene expression patterns and biochemical characteristics provide new information about the functional specialization among BmCDA6, BmCDA7 and BmCDA8 proteins.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.5
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available