Further Study on the Two Pivotal Parts of Hlg2 for the Full Hemolytic Activity of Staphylococcal [gamma]-Hemolysin

• Published in: Bioscience, biotechnology, and biochemistry Vol. 62; no. 9; p. 1745
• Main Authors: YOKOTA, Kenji, SUGAWARA, Noriko, NARIYA, Hirofumi, KANEKO, Jun, TOMITA, Toshio, KAMIO, Yoshiyuki
• Format: Journal Article
• Language: English
• Published: Tokyo Oxford University Press 01.09.1998
• ISSN: 0916-8451; 1347-6947

Staphylococcal γ-hemolysin consists of LukF of 34 kDa and Hlg2 (or HγII) of 32 kDa, which cooperatively lyse human and rabbit erythrocytes. Our previous data showed that the 5-residue segment K23R24L25A26I27 of Hlg2 is pivotal for the hemolytic activity [Nariya, H. and Kamio, Y., Biosci. Biotechnol. Biochem., 59, 1603-1604 (1997)]. Here, we identify an additional amino acid residue in Hlg2 necessary for the full γ-hemolysin activity by measuring the toxin activity of Hlg2 mutants in the presence of LukF. The data obtained showed that Arg217 of Hlg2 is an additional pivotal amino acid residue besides the KRLAI segment for the full Hlg2-specific function in γ-hemolysin. We also report evidence that the Hlg2 mutants showing a low or null hemolytic activity in the presence of LukF towards human erythrocytes had low or no binding activity to the cells, resulting in failure of formation of the ring-shaped pore-forming complex on the erythrocytes.