Biomaterial Database

Targeting of heterologous membrane proteins into proliferated internal membranes in Saccharomyces cerevisiae. 1995

N E Wittekindt, and F E Würgler, and C Sengstag

Institute of Toxicology, Swiss Federal Institute of Technology, Schwerzenbach, Switzerland.

Overproduction of chimeric proteins containing the HMG2/1 peptide, which comprises the seven transmembrane domains of Saccharomyces cerevisiae 3-hydroxy-3-methylglutaryl-CoA reductase isozymes 1 and 2, has previously been observed to induce the proliferation of internal endoplasmic reticulum-like membranes. In order to exploit this amplified membrane surface area for the accommodation of heterologous microsomal proteins, we fused sequences coding for human cytochrome P4501A1 (CYP1A1) to sequences encoding the HMG2/1 peptide and expressed the hybrid genes in yeast. The heterologous hybrid proteins were targeted into strongly proliferated membranes, as shown by electron microscopic and immunofluorescent analysis. Fusion proteins comprising the whole CYP1A1 polypeptide (HMG2/1-CYP1A1) exhibited 7-ethoxyresorufin-O-deethylase activity, whereas fusion proteins lacking the N-terminal 56 amino acids of CYP1A1 (HMG2/1-delta CYP1A1) were inactive and appeared to be unable to incorporate protoheme. Similar amounts of heterologous protein were detected in cells expressing HMG2/1-CYP1A1, HMG2/1-delta CYP1A1 and CYP1A1, respectively. Replacement of the N-terminal membrane anchor domain of human NADPH-cytochrome P450 oxidoreductase by the HMG2/1 peptide also resulted in a functional fusion enzyme, which was able to interact with HMG2/1-CYP1A1 and the yeast endogenous P450 enzyme lanosterol-14 alpha-demethylase.

UI	MeSH Term	Description	Entries
D007425	Intracellular Membranes	Thin structures that encapsulate subcellular structures or ORGANELLES in EUKARYOTIC CELLS. They include a variety of membranes associated with the CELL NUCLEUS; the MITOCHONDRIA; the GOLGI APPARATUS; the ENDOPLASMIC RETICULUM; LYSOSOMES; PLASTIDS; and VACUOLES.	Membranes, Intracellular,Intracellular Membrane,Membrane, Intracellular
D007527	Isoenzymes	Structurally related forms of an enzyme. Each isoenzyme has the same mechanism and classification, but differs in its chemical, physical, or immunological characteristics.	Alloenzyme,Allozyme,Isoenzyme,Isozyme,Isozymes,Alloenzymes,Allozymes
D008565	Membrane Proteins	Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.	Cell Membrane Protein,Cell Membrane Proteins,Cell Surface Protein,Cell Surface Proteins,Integral Membrane Proteins,Membrane-Associated Protein,Surface Protein,Surface Proteins,Integral Membrane Protein,Membrane Protein,Membrane-Associated Proteins,Membrane Associated Protein,Membrane Associated Proteins,Membrane Protein, Cell,Membrane Protein, Integral,Membrane Proteins, Integral,Protein, Cell Membrane,Protein, Cell Surface,Protein, Integral Membrane,Protein, Membrane,Protein, Membrane-Associated,Protein, Surface,Proteins, Cell Membrane,Proteins, Cell Surface,Proteins, Integral Membrane,Proteins, Membrane,Proteins, Membrane-Associated,Proteins, Surface,Surface Protein, Cell
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D010957	Plasmids	Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.	Episomes,Episome,Plasmid
D011993	Recombinant Fusion Proteins	Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.	Fusion Proteins, Recombinant,Recombinant Chimeric Protein,Recombinant Fusion Protein,Recombinant Hybrid Protein,Chimeric Proteins, Recombinant,Hybrid Proteins, Recombinant,Recombinant Chimeric Proteins,Recombinant Hybrid Proteins,Chimeric Protein, Recombinant,Fusion Protein, Recombinant,Hybrid Protein, Recombinant,Protein, Recombinant Chimeric,Protein, Recombinant Fusion,Protein, Recombinant Hybrid,Proteins, Recombinant Chimeric,Proteins, Recombinant Fusion,Proteins, Recombinant Hybrid
D003577	Cytochrome P-450 Enzyme System	A superfamily of hundreds of closely related HEMEPROTEINS found throughout the phylogenetic spectrum, from animals, plants, fungi, to bacteria. They include numerous complex monooxygenases (MIXED FUNCTION OXYGENASES). In animals, these P-450 enzymes serve two major functions: (1) biosynthesis of steroids, fatty acids, and bile acids; (2) metabolism of endogenous and a wide variety of exogenous substrates, such as toxins and drugs (BIOTRANSFORMATION). They are classified, according to their sequence similarities rather than functions, into CYP gene families (>40% homology) and subfamilies (>59% homology). For example, enzymes from the CYP1, CYP2, and CYP3 gene families are responsible for most drug metabolism.	Cytochrome P-450,Cytochrome P-450 Enzyme,Cytochrome P-450-Dependent Monooxygenase,P-450 Enzyme,P450 Enzyme,CYP450 Family,CYP450 Superfamily,Cytochrome P-450 Enzymes,Cytochrome P-450 Families,Cytochrome P-450 Monooxygenase,Cytochrome P-450 Oxygenase,Cytochrome P-450 Superfamily,Cytochrome P450,Cytochrome P450 Superfamily,Cytochrome p450 Families,P-450 Enzymes,P450 Enzymes,Cytochrome P 450,Cytochrome P 450 Dependent Monooxygenase,Cytochrome P 450 Enzyme,Cytochrome P 450 Enzyme System,Cytochrome P 450 Enzymes,Cytochrome P 450 Families,Cytochrome P 450 Monooxygenase,Cytochrome P 450 Oxygenase,Cytochrome P 450 Superfamily,Enzyme, Cytochrome P-450,Enzyme, P-450,Enzyme, P450,Enzymes, Cytochrome P-450,Enzymes, P-450,Enzymes, P450,Monooxygenase, Cytochrome P-450,Monooxygenase, Cytochrome P-450-Dependent,P 450 Enzyme,P 450 Enzymes,P-450 Enzyme, Cytochrome,P-450 Enzymes, Cytochrome,Superfamily, CYP450,Superfamily, Cytochrome P-450,Superfamily, Cytochrome P450
D004271	DNA, Fungal	Deoxyribonucleic acid that makes up the genetic material of fungi.	Fungal DNA
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D006903	Hydroxymethylglutaryl CoA Reductases	Enzymes that catalyze the reversible reduction of alpha-carboxyl group of 3-hydroxy-3-methylglutaryl-coenzyme A to yield MEVALONIC ACID.	HMG CoA Reductases,3-Hydroxy-3-methylglutaryl CoA Reductase,HMG CoA Reductase,Hydroxymethylglutaryl CoA Reductase,3 Hydroxy 3 methylglutaryl CoA Reductase,CoA Reductase, 3-Hydroxy-3-methylglutaryl,Reductase, 3-Hydroxy-3-methylglutaryl CoA