Molecular cloning and characterisation of a thioester-containing α2-macroglobulin (α2-M) from the haemocytes of mud crab Scylla serrata

Comparison of the thioester domain and adjacent regions of the alpha2-macroglobulin from different South Atlantic crustaceans

“…On the other hand, the deduced amino acidic sequences of the native estuarine crabs also showed a significant identity between them (88% identity) and with those of the penaeid shrimps and M. rosenbergii (about 55% identity). Surprisingly, both crab sequences had a higher identity with those of penaeid and freshwater shrimps than with that of the crab S. serrata (DQ347954, 42% identity [6]), the only a2M gene sequence currently available in a crab.…”

“…The first cDNA encoding for a2M was reported in the kuruma prawn Marsupenaeus japonicus and was constitutively expressed in their haemocytes [5]. After this first report, other complete sequences encoding for a2M were identified only very recently in two other decapods, the mud crab Scylla serrata [6] and the black tiger shrimp Penaeus monodon [7]. The aim of the present study was to detect and compare sequences encoding to the a2M thioester domain and adjacent regions in two South Atlantic penaeid shrimps (the pink shrimp Farfantepenaeus paulensis and the white shrimp Litopenaeus schmitti) and two estuarine crabs (Chasmagnathus granulata and Goniopsis cruentata).…”

Quantitative gene expression and in situ localization of scygonadin potentially associated with reproductive immunity in tissues of male and female mud crabs, Scylla paramamosain

“…Subsequently, scyllin was found from the hemolymph of S. serrata [15], callinectin from blue crab hemocytes [16], crustin from the granular hemocytes of the shore crab C. maenas [17] and further characterized from S. paramamosain [18]. In addition, various proteins, which are important in invertebrate innate defense mechanisms, such as prophenoloxidase and a2-macroglobulin are detected in the hemocytes of S. serrata and their mRNA transcripts are increased significantly post-lipopolysaccharide (LPS) injection [19,20]. Scygonadin (Scy), an anionic AMP was isolated from the seminal plasma of the mud crab S. paramamosain in our laboratory [21,22].Its recombinant product is active against both grampositive and gram-negative bacteria [23].…”

Identification and agglutination properties of hemocyanin from the mud crab (Scylla serrata)

“…Over the past several years, several non-specific immune proteins in crab species have been identified including antimicrobial peptide [4e6], prophenoloxidase [7], anti-lipopolysaccharide factor (ALF) [8e10], antioxidant enzyme [11], superoxide dismutase [12] and a2-macroglobulin [13]. Recently, hemocyanin, the main protein component of hemolymph from mollusks and arthropods, was reported as a novel and important defense molecule of the nonspecific innate immune system [14,15].…”