title: A novel methodology for enhanced and consistent heterologous expression of unmodified human cytochrome P450 1B1 (CYP1B1).
abstract: Cytochrome P450 1B1 (CYP1B1) is a universal cancer marker and is implicated in many other disorders. Mutations in CYP1B1 are also associated with childhood blindness due to primary congenital glaucoma (PCG). To understand the CYP1B1 mediated etiopathology of PCG and pathomechanism of various cancers, it is important to carry out its functional studies. Heterologous expression of CYP1B1 in prokaryotes is imperative because bacteria yield a higher amount of heterologous proteins in lesser time and so the expressed protein is ideal for functional studies. In such expression system there is no interference by other eukaryotic proteins. But the story is not that simple as expression of heterologous CYP1B1 poses many technical difficulties. Investigators have employed various modifications/deletions of CYP N-terminus to improve CYP1B1 expression. However, the drawback of these studies is that it changes the original protein and, as a result, invalidates functional studies. The present study examines the role of various conditions and reagents in successful and consistent expression of sufficient quantities of unmodified/native human CYP1B1 in E. coli. We aimed at expressing CYP1B1 in various strains of E. coli and in the course developed a protocol that results in high expression of unmodified protein sufficient for functional/biophysical studies. We examined CYP1B1 expression with respect to different expression vectors, bacterial strains, types of culture media, time, Isopropyl β-D-1-thiogalactopyranoside concentrations, temperatures, rotations per minute, conditioning reagents and the efficacy of a newly described technique called double colony selection. We report a protocol that is simple, easy and can be carried out in any laboratory without the requirement of a fermentor. Though employed for CYP1B1 expression, this protocol can ideally be used to express any eukaryotic membrane protein.
authors.affiliation: Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India; Medical Biotechnology Laboratory, Dr. B. R. Ambedkar Centre for Biomedical Research, University of Delhi, North Campus, Delhi, India; Laboratory for Molecular Reproduction and Genetics, Department of Anatomy, All India Institute of Medical Sciences, Ansari Nagar, India.
authors.forename: Muneeb A
authors.initials: MA
authors.lastname: Faiq
authors.affiliation: Medical Biotechnology Laboratory, Dr. B. R. Ambedkar Centre for Biomedical Research, University of Delhi, North Campus, Delhi, India.
authors.forename: Mashook
authors.initials: M
authors.lastname: Ali
authors.affiliation: Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India.
authors.forename: Tanuj
authors.initials: T
authors.lastname: Dada
authors.affiliation: Laboratory for Molecular Reproduction and Genetics, Department of Anatomy, All India Institute of Medical Sciences, Ansari Nagar, India.
authors.forename: Rima
authors.initials: R
authors.lastname: Dada
authors.affiliation: Medical Biotechnology Laboratory, Dr. B. R. Ambedkar Centre for Biomedical Research, University of Delhi, North Campus, Delhi, India.
authors.forename: Daman
authors.initials: D
authors.lastname: Saluja
mesh_terms: D003470:Culture Media; D065633:Cytochrome P-450 CYP1B1 / Q000096:biosynthesis* / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D005786:Gene Expression Regulation / Q000235:genetics*; D005901:Glaucoma / Q000151:congenital / Q000235:genetics* / Q000473:pathology; D006801:Humans; D008565:Membrane Proteins / Q000235:genetics; D009154:Mutation; D011994:Recombinant Proteins / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D003470:Culture Media; D008565:Membrane Proteins; D011994:Recombinant Proteins; C585496:CYP1B1 protein, human; D065633:Cytochrome P-450 CYP1B1