Urbanization has the potential to dramatically affect insect populations worldwide, although its effects on pollinator populations are just beginning to be understood. We compared the immunocompetency of honey bees sampled from feral (wild-living) and managed (beekeeper-owned) honey bee colonies. We sampled foragers from feral and managed colonies in rural, suburban, and urban landscapes in and...

Clip domain serine protease homologs (SPHs) are positive and negative regulators of Anopheles gambiae immune responses mediated by the complement-like protein TEP1 against Plasmodium malaria parasites and other microbial infections. We have previously reported that the SPH CLIPA2 is a negative regulator of the TEP1-mediated response by showing that CLIPA2 knockdown (kd) enhances mosquito resist...

Clip-domain serine proteases (SPs) are the essential components of extracellular signaling cascades in various biological processes, especially in embryonic development and the innate immune responses of invertebrates. They consist of a chymotrypsin-like SP domain and one or two clip domains at the N-terminus. Prophenoloxidase-activating factor (PPAF)-II, which belongs to the noncatalytic clip-...

Honey bees (Apis mellifera) have become a model system for studies on the influence of genetic diversity on disease. Honey bee queens mate with a remarkably high number of males-up to 29 in the current study-from which they produce a colony of genetically diverse daughter workers. Recent evidence suggests a significant benefit of intracolony genetic diversity on disease resistance. Here, we exp...

Many parasites, including important species that affect humans and livestock, must survive the harsh environment of insect guts to complete their life-cycle. Hence, understanding how insects protect themselves against such parasites has immediate practical implications. Previously, such protection has been thought to consist mainly of mechanical structures and the action of lectins. However, re...

This paper reports the isolation of phenoloxidase-negative mutants of the white-rot fungus Phanerochaete chrysosporium and the results of a survey of idiophasic functions among these mutants. The mutant strains were isolated from a medium containing o-anisidine after gamma irradiation of wild-type spores and fell into four classes, divided by the manner in which they mineralized 14C-lignin whea...

Melanization, which is brought about by the activation of the prophenoloxidase (proPO) cascade, plays an essential role in the invertebrate immune response. It is triggered by minute amounts of microbial cell wall components leading to the activation of the enzyme proPO, which converts phenols into quinones and eventually resulting to the formation of melanin. Recent studies however, revealed t...

Phenoloxidase (PO) from the humoral fluid of amphioxus B. belcheri tsingtauense was purified using a sequential combination of ammonium sulphate precipitation, Sephadex G-200 chromatography and DEAE Sepharose Fast Flow chromatography. In PAGE, the purified enzyme exhibited a single band of 150 kDa under non-reducing conditions, and was resolved to three bands with molecular masses of 72, 46 and...