#melanisation

[mbimphblog]

DETECTION AND CHARACTERIZATION OF PHENOLOXIDASE FROM THE LARVAL HAEMOLYMPH OF BLOW FLY, Hemipyrellia tagaliana IN RESPONSE TO NON-SELF MOLECULES | UTTAR PRADESH JOURNAL OF ZOOLOGY

In the absence of an advanced immune system in insects, the melanisation process is the most widespread and one of the most successful methods used by insects to identify pathogens or foreign non-self substances. Thus the main enzyme involved in phenoloxidase (PO) melanin biosynthesis plays a crucial role in insect immunity. In this analysis, the larval blowfly haemolymph (Hemipyrellia tagaliana) was used to demonstrate the existence and activation of prophenoloxidase. In the oxidation assays carried out to test the existence of prophenoloxidase using phenolic substrates, the haemolymph showed favourable outcomes. Phenylthiourea, an inhibitor of PO activity, has been shown to repress this PO activity, whereas activity has been increased when exposed to microbial components such as laminarin, LPS of different bacterial organisms, and zymogen. The results suggested that when exogenous proteases and detergents were added into the assay system, this enzyme (PO) existed in the zymogen state and was activated by proteolytic cleavage. Its calcium-dependent existence was demonstrated by increased PO activity in the presence of Ca2+. These findings conclude that in the larval haemolymph of H, a zymogen of phenoloxidase is found. Tagaliana, which is triggered when exposed to foreign non-self-substances and pathogens by proteolytic cleavage. Please see the link :- https://mbimph.com/index.php/UPJOZ/article/view/1622

[mbimphblog]

DETECTION AND CHARACTERIZATION OF PHENOLOXIDASE FROM THE LARVAL HAEMOLYMPH OF BLOW FLY, Hemipyrellia tagaliana IN RESPONSE TO NON-SELF MOLECULES | UTTAR PRADESH JOURNAL OF ZOOLOGY

In the deficiency of advanced immune mechanism in insects, the most common and one of the efficient methods used by insects in recognising pathogens or foreign non-self substances is the melanisation process. The primary enzyme involved in melanin biosynthesis by phenoloxidase (PO) thus plays a vital role in insect immunity. In the present study, larval haemolymph of the blowfly, (Hemipyrellia tagaliana) were used to demonstrate the presence of prophenoloxidase and its activating system. The haemolymph showed favourable results in the oxidation assays carried out to test the presence of prophenoloxidase using phenolic substrates. This PO activity was shown to be repressed by phenylthiourea, an inhibitor of PO activity, while the activity was increased when exposed to microbial components such as laminarin, LPS from various bacterial species and zymogen. The results indicated that this enzyme (PO) existed in zymogen state and was activated by proteolytic cleavage when exogenous proteases and detergents were introduced in the assay system. An increased PO activity in the presence of Ca2+ showed its calcium-dependent nature. These results conclude that a zymogen of phenoloxidase is found in the larval haemolymph of the H. tagaliana, which is activated by proteolytic cleavage when exposed to foreign non-self-substances and pathogens.

Please see the link :-  https://mbimph.com/index.php/UPJOZ/article/view/1622