Characteristics of surfactant protein A and D binding to lipoteichoic acid and peptidoglycan, 2 major cell wall components of gram-positive bacteria.
Infection with gram-positive bacteria is a major cause of pneumonia. Surfactant proteins A (SP-A) and D (SP-D) are thought to play an important role in the innate immunity of the lung. Both proteins can bind to gram-positive bacteria. Until now, it was not known with which surface component(s) of gram-positive bacteria SP-A and SP-D interact. Lipoteichoic acid (LTA) and peptidoglycan (PepG) are components of the cell wall of gram-positive bacteria. By use of a solid phase-based binding assay, LTA of Bacillus subtilis was shown to be bound by SP-D but not by SP-A. Unmodified PepG of Staphylococcus aureus was bound by SP-D. SP-D binding to both LTA and PepG was calcium dependent and carbohydrate inhibitable. These results indicate that SP-D interacts with gram-positive bacteria via binding to the cell wall components LTA and PepG and that the carbohydrate recognition domain is responsible for this binding.
van de Wetering
J K
JK
Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Graduate School of Animal Health, Utrecht University, 3508 TD Utrecht, The Netherlands. j.k.vandeweterig@vet.uu.nl
van Eijk
M
M
van Golde
L M
LM
Hartung
T
T
van Strijp
J A
JA
Batenburg
J J
JJ
D000818:Animals; D001412:Bacillus subtilis / Q000378:metabolism*; D001667:Binding, Competitive; D002118:Calcium / Q000378:metabolism; D050260:Carbohydrate Metabolism; D002473:Cell Wall / Q000737:chemistry; D006023:Glycoproteins / Q000378:metabolism*; D006801:Humans; D008070:Lipopolysaccharides / Q000378:metabolism*; D010457:Peptidoglycan / Q000378:metabolism*; D011510:Proteolipids / Q000378:metabolism*; D037662:Pulmonary Surfactant-Associated Protein A; D037663:Pulmonary Surfactant-Associated Protein D; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants / Q000378:metabolism*; D013211:Staphylococcus aureus / Q000378:metabolism*; D013682:Teichoic Acids / Q000378:metabolism*
D006023:Glycoproteins; D008070:Lipopolysaccharides; D010457:Peptidoglycan; D011510:Proteolipids; D037662:Pulmonary Surfactant-Associated Protein A; D037663:Pulmonary Surfactant-Associated Protein D; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants; D013682:Teichoic Acids; C009900:lipoteichoic acid; D002118:Calcium