Glycerophospholipid:cholesterol acyltransferase complexed with lipopolysaccharide (GCAT‐LPS) of Aeromonas salmonicida produces lysophospholipids in salmonid red cell membranes: a probable haemolytic mechanism

• Published in: Journal of Fish Diseases
• Main Authors: RØSJØ, C., SALTE, R., THOMASSEN, M. S., EGGSET, G.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 1993
• Subjects: Atlantic salmon; Salmo salar
• Online Access: http://dx.doi.org/10.1111/j.1365-2761.1993.tb00852.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1365-2761.1993.tb00852.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1365-2761.1993.tb00852.x

Abstract. The enzymic activity of GCAT‐LPS was studied using whole blood ( in vivo ), citrated blood or washed red blood cells as substrate. Results demonstrated in vitro and in vivo haemolysis of Atlantic salmon, Salmo salar L., red blood cells, and in vitro haemolysis of rainbow trout, Oncorhynchus mykiss (Walbaum), red blood cells, by purified GCAT‐LPS. Haemolysis coincided with 10% or more lysophospholipids, as a per cent of total phospholipids, in the red cell membranes. Addition of soybean lysophosphatidylcholine to citrated whole blood from salmon caused haemolysis. This suggests that it is the observed accumulation of lysophospholipids, caused by the enzymic activity of GCAT‐LPS, which leads to lysis of salmonid red blood cells. When membranes were used as substrate, GCAT‐LPS seemed to express acyltransferase and possibly some phospholipase activity, while accumulation of lysophospholipids suggests that the lysophospholipase activity is inhibited or severely suppressed. Deacylation of both phosphatidylcholine and phosphatidylethanolamine was observed, indicating that both phospholipids are substrates for the enzyme.