Phenoloxidase and myeloperoxidase activity in the haemocytes and serum of Chlamys farreri
Sun HushanLi Guangyou (Ynatai Normal College,Yantai 264025)(The First Institute of Oceanography SOA, Qingdao 266003)
The phenoloxidase (PO) and myeloperoxidase(MPO)in the haemocytes and haemolymph of the Chlamys frrreri were studied with the method of cytochemical localisation using electron-microscopy and specreophotometer.The results show that 2 kinds of granules,300430 nm and 130200 nm in diameter,in cytoplasm are strongly positive to PO. The secondary lysosomes and the small granules are strongly positive to MPO. The results of biochemical test show that there are PO and MPO in haemolymph and there is only MPO in haemocytes. PO is present in an inactive form (proPO) in haemocyres. The enzyme activities of MPO in haemocytes is 3.5 fold as much as those in the haemolymph. Halide-independent MPO in haemolymph is 107.2 U using TMB as the substrate, and halide-dependent MPO in haemolymph is 53.6 U using diethanolamine as the substrate.The optimum pH of PO and MPO in haemolymph are 6.0 and 6.5 and the optimum temperatures of PO and MPO in haemolymph are 45 and 35.