The majority of staphylococci produce biofilm on medical devices, which is the main mechanism to infect humans. Staphylococcal biofilms attach to abiotic or biotic surfaces, forming aggregates and protecting themselves against the immune system and the antimicrobial compounds of the host. Few studies on biofilm formation mechanism in Staphylococcus epidermidis and other coagulase-negative staphylococci (CNS) have been performed; however, there is a great interest in studying and controlling biofilm formation of this genus. This chapter exhibits the state of the art on biofilm formation in S. epidermidis and other staphylococcal species. The main goal of this chapter is to recognize the importance of biofilm formation in Staphylococcus. The participating molecules in staphylococcal biofilm formation are described. Currently, biofilm producer strains of Staphylococcus and mainly CNS have been frequently isolated at hospitals, causing significant economic losses. This chapter includes promising solutions in order to prevent medical device-associated infections, as the development of medical devices possessing anti-biofilm materials or surfaces that act against the adhesion or viability of the microorganisms.
Part of the book: Microbial Biofilms
Polycyclic aromatic hydrocarbons (PAHs)‐contaminated soils have been a concern during last decades; consequently, physicochemical and biological technologies have emerged and evolved with the aim of remediating them. Particularly, biological technologies are considered promising since they are low cost, safe and environmentally friendly. However, their results so far have been diverse and scattered. This chapter includes a review of the current status on bioaugmentation, biostimulation and bioattenuation techniques, which have been applied in PAHs‐contaminated agricultural soils during the last decades. Successes and failures in PAHs remediation applied at microcosm and field levels are exhibited. Furthermore, the effects of microbial inoculum, the soil organic matter and the particle size of the aggregates on the PAHs’ availability and on the subsequent microbial biodegradation are reviewed. Finally, agricultural management systems are considered in the prediction of the behaviour and the end‐point of some contaminants, as well as in the success of applying a biological technique.
Part of the book: Soil Contamination
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 wall–anchored (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.
Part of the book: The Rise of Virulence and Antibiotic Resistance in Staphylococcus aureus