TY - JOUR
T1 - Demonstration of nitric oxide synthase activity in crustacean hemocytes and anti-microbial activity of hemocyte-derived nitric oxide
AU - Yeh, Feng Ching
AU - Wu, Su Hua
AU - Lai, Chi Yung
AU - Lee, Chi Ying
PY - 2006/5
Y1 - 2006/5
N2 - We determined the biochemical characteristics of nitric oxide synthase (NOS) in hemocytes of the crayfish Procambarus clarkii and investigated the roles of hemocyte-derived NO in host defense. Biochemical analysis indicated the presence of a Ca2+-independent NOS activity, which was elevated by lipopolysaccharide (LPS) treatment. When bacteria (Staphylococcus aureus) and hemocytes were co-incubated, adhesion of bacteria to hemocytes was observed. NO donor sodium nitroprusside (SNP) significantly increased the numbers of hemocytes to which bacteria adhered. Similarly, LPS elicited bacterial adhesion and the LPS-induced adhesion was prevented by NOS inhibitor NG-monomethyl-l-arginine (l-NMMA). Finally, plate count assay demonstrated that addition of LPS to the hemocytes/bacteria co-incubation resulted in a significant decrease in bacterial colony forming unit (CFU), and that l-NMMA reversed the decreasing effect of LPS on CFU. The combined results demonstrate the presence of a Ca2+-independent LPS-inducible NOS activity in crayfish hemocytes and suggest that hemocyte-derived NO is involved in promoting bacterial adhesion to hemocytes and enhancing bactericidal activity of hemocytes.
AB - We determined the biochemical characteristics of nitric oxide synthase (NOS) in hemocytes of the crayfish Procambarus clarkii and investigated the roles of hemocyte-derived NO in host defense. Biochemical analysis indicated the presence of a Ca2+-independent NOS activity, which was elevated by lipopolysaccharide (LPS) treatment. When bacteria (Staphylococcus aureus) and hemocytes were co-incubated, adhesion of bacteria to hemocytes was observed. NO donor sodium nitroprusside (SNP) significantly increased the numbers of hemocytes to which bacteria adhered. Similarly, LPS elicited bacterial adhesion and the LPS-induced adhesion was prevented by NOS inhibitor NG-monomethyl-l-arginine (l-NMMA). Finally, plate count assay demonstrated that addition of LPS to the hemocytes/bacteria co-incubation resulted in a significant decrease in bacterial colony forming unit (CFU), and that l-NMMA reversed the decreasing effect of LPS on CFU. The combined results demonstrate the presence of a Ca2+-independent LPS-inducible NOS activity in crayfish hemocytes and suggest that hemocyte-derived NO is involved in promoting bacterial adhesion to hemocytes and enhancing bactericidal activity of hemocytes.
UR - http://www.scopus.com/inward/record.url?scp=33646065312&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=33646065312&partnerID=8YFLogxK
U2 - 10.1016/j.cbpb.2006.01.007
DO - 10.1016/j.cbpb.2006.01.007
M3 - Article
C2 - 16516518
AN - SCOPUS:33646065312
VL - 144
SP - 11
EP - 17
JO - Comparative Biochemistry and Physiology - B Biochemistry and Molecular Biology
JF - Comparative Biochemistry and Physiology - B Biochemistry and Molecular Biology
SN - 1096-4959
IS - 1
ER -