Phospholipase C from Clostridium novyi type A. I.

Area of Science:

• Biochemistry
• Enzymology
• Microbiology

Background:

• Clostridium novyi (oedematiens) type A produces phospholipase C, an enzyme with hemolytic activity.
• Understanding the specific activity and substrate preferences of this enzyme is crucial for its characterization.

Purpose of the Study:

• To purify Phospholipase C (EC 3.1.4.3) from Clostridium novyi (oedematiens) type A.
• To characterize the enzyme's activity, substrate specificity, and hemolytic mechanism.

Main Methods:

• Enzyme purification using ammonium sulfate precipitation, DEAE-Sephadex batch treatment, and Sephadex G-100 chromatography.
• Assessing enzyme activity by measuring hydrolysis rates of various phospholipids.
• Evaluating hemolytic activity against horse red blood cells.

Main Results:

• Achieved a 2000-fold purification of Phospholipase C with a specific activity of 95 μmol/min/mg protein towards phosphatidylcholine.
• The purified enzyme was free of protease, lipase, and delta-hemolysin.
• Phosphatidylcholine was the preferred substrate, with significant stimulation of activity by sodium deoxycholate and divalent cations (Mg2+, Ca2+).
• The enzyme demonstrated hemolytic activity through the hydrolysis of phosphatidylcholine, sphingomyelin, and phosphatidylethanolamine.

Conclusions:

• The purified Phospholipase C from Clostridium novyi is a potent phosphatidylcholine-specific enzyme.
• Sodium deoxycholate and divalent cations are essential activators for its phosphatidylcholine-hydrolyzing activity.
• The enzyme's hydrolysis of specific phospholipids contributes to its observed hemolytic effect on red blood cells.