title: Heterologous expression of a hydrophobin HFB1 and evaluation of its contribution to producing stable foam.
abstract: Hydrophobins are small secreted proteins belong to filamentous fungi. These proteins possess a unique ability to self-assemble at air/water interfaces. Hydrophobins have a broad range of biotechnological applications such as stabilizing emulsions and foams, immobilizing proteins on a surface, designing biosensors, affinity tag for protein purification, and drug delivery. We have successfully expressed HFB1 from Trichoderma reesei belonged to class II of hydrophobins in Pichia pastoris. The recombinant gene was under the control of the methanol-inducible AOX1 promoter (alcohol oxidase 1) in the pPICZAα vector. The amount of secreted HFB1 was increased in 90-h using methanol induction. The recombinant HFB1 was purified based on the presence of His-tag and foam formation. Furthermore, HFB1 was able to produce macro and micro stable air bubbles in the liquid due to the presence of hydrophobic patches on its surface. The liquid medium containing HFB1 becomes turbid after shaking, and then the stable bubbles are formed and remained for three weeks.
authors.affiliation: Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran.
authors.forename: Azadeh
authors.initials: A
authors.lastname: Lohrasbi-Nejad
authors.affiliation: Department of Biotechnology, Institute of Science, High Technology and Environmental Science, Graduate University of Advanced Technology, Kerman, Iran.
authors.forename: Masoud
authors.initials: M
authors.lastname: Torkzadeh-Mahani
authors.affiliation: Department of Biochemistry, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, Iran. Electronic address: saman_h@modares.ac.ir.
authors.forename: Saman
authors.initials: S
authors.lastname: Hosseinkhani
mesh_terms: D005656:Fungal Proteins / Q000737:chemistry* / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D015870:Gene Expression; D057927:Hydrophobic and Hydrophilic Interactions; D010843:Pichia / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D013501:Surface-Active Agents / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D014242:Trichoderma / Q000235:genetics*
chemical_list: D005656:Fungal Proteins; D011994:Recombinant Proteins; D013501:Surface-Active Agents
keywords: HFB1; Heterologous expression; Hydrophobin; Pichia pastoris