Surface Proteins of Staphylococcus aureus

Abstract

Staphylococcus aureus is a commensal bacterium that causes infections such as sepsis, endocarditis, and pneumonia. S. aureus can express a variety of virulence factors, including surface proteins. Surface proteins are characterized by presence of a Sec-dependent signal sequence at the amino terminal, and the sorting signal domain. Surface proteins are covalently attached to peptidoglycan and they are commonly known as cell wallanchored (CWA) proteins. CWA proteins have many functions and participate in the pathogenesis of S. aureus. Furthermore, these proteins have been proposed as therapeutic targets for the generation of vaccines. In this chapter, different topics related to CWA proteins of S. aureus are addressed. The molecular structure of CWA proteins and their role as virulence factors of S. aureus are described. Furthermore, the involvement of CWA proteins in the processes of adhesion, invasion of host cells and tissues, evasion of the immune response, and the formation of biofilm is discussed. In addition, the role of CWA proteins in skin infection and the proposal to use them as potential vaccine antigens are described. The information contained in this chapter will help the readers to understand the biology of CWA proteins and to recognize the importance of surface molecules of S. aureus.

Natural Human Immunity Against Staphylococcal Protein A Relies on Effector Functions Triggered by IgG3

“…Correct opsonization of S. aureus by antibodies is a pivotal step of staphylococcal clearance ( 4 , 5 , 9 ). Several cell wall-anchored proteins are described as potential targets for opsonizing antibodies ( 60 ), but this is controversial for SpA. Offering additional high-affinity binding sites for the Fc region on the bacterial surface, SpA severely interferes with antibody deposition, ultimately hampering opsonophagocytosis ( 42 ).…”

Staphylococcus aureus adhesion to the host

“…The L-lectin/cadherin-like family of proteins also only contains one member, the serine-rich adhesin of platelets (SraP), which is composed of an N-terminal short serine-rich repeat region followed by the ligandbinding region that exhibits affinity for human platelets. 32,49,50 This region comprises four subdomains that are separately folded forming a bent and rigid rod. 32 Three domains, two cadherin-like and one β-grasp fold domain, extend the legume-lectin domain outward, which can then adhere to glycoproteins on mammalian cell surfaces containing Nacetyl neuraminic acid.…”

Molecular Modeling and Docking Studies of Some Benzodiazole Derivatives on the Protein of Staphylococcus aureus

“…The Staphylococcus aureus is a gram-positive bacteria that colonizes the nasal cavity of 20-30% of the human population without causing any apparent disease [1]. The surface proteins of S. aureus are covalently attached to the peptidoglycan, and for that reason, they are named as cell wall-anchored [2]. Based on its molecular structure and arrangement, the CWA proteins of S. aureus have been classified into four families: the MSCRAMM family, the NEAT motif family, the three-helical bundle family, and the G5-E repeat family.…”