title: Molecular Characteristics and Biological Functions of Surface-Active and Surfactant Proteins.
abstract: Many critical biological processes take place at hydrophobic:hydrophilic interfaces, and a wide range of organisms produce surface-active proteins and peptides that reduce surface and interfacial tension and mediate growth and development at these boundaries. Microorganisms produce both small lipid-associated peptides and amphipathic proteins that allow growth across water:air boundaries, attachment to surfaces, predation, and improved bioavailability of hydrophobic substrates. Higher-order organisms produce surface-active proteins with a wide variety of functions, including the provision of protective foam environments for vulnerable reproductive stages, evaporative cooling, and gas exchange across airway membranes. In general, the biological functions supported by these diverse polypeptides require them to have an amphipathic nature, and this is achieved by a diverse range of molecular structures, with some proteins undergoing significant conformational change or intermolecular association to generate the structures that are surface active.
authors.affiliation: Discipline of Pharmacology, School of Medical Sciences and Australian Institute for Nanoscale Science and Technology, University of Sydney, NSW 2006, Australia; email: margaret.sunde@sydney.edu.au , chi.pham@sydney.edu.au.
authors.forename: Margaret
authors.initials: M
authors.lastname: Sunde
authors.affiliation: Discipline of Pharmacology, School of Medical Sciences and Australian Institute for Nanoscale Science and Technology, University of Sydney, NSW 2006, Australia; email: margaret.sunde@sydney.edu.au , chi.pham@sydney.edu.au.
authors.forename: Chi L L
authors.initials: CLL
authors.lastname: Pham
authors.affiliation: School of Life and Environmental Sciences and Australian Institute for Nanoscale Science and Technology, University of Sydney, NSW 2006, Australia; email: ann.kwan@sydney.edu.au.
authors.forename: Ann H
authors.initials: AH
authors.lastname: Kwan
mesh_terms: D000818:Animals; D001419:Bacteria / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D002364:Caseins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D005658:Fungi / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D006023:Glycoproteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D008322:Mammals; D008565:Membrane Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D009363:Neoplasm Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D010750:Phosphoproteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011487:Protein Conformation; D011663:Pulmonary Surfactants / Q000737:chemistry* / Q000378:metabolism; D013499:Surface Properties; D013501:Surface-Active Agents / Q000737:chemistry* / Q000378:metabolism; D014867:Water / Q000737:chemistry / Q000378:metabolism
chemical_list: C485599:BPIFA1 protein, human; C472128:BPIFA4P protein, human; D002364:Caseins; D006023:Glycoproteins; D008565:Membrane Proteins; D009363:Neoplasm Proteins; D010750:Phosphoproteins; D011663:Pulmonary Surfactants; D013501:Surface-Active Agents; D014867:Water
keywords: bioemulsifier; interfacial; surface tension; surface-active; surfactant