complete protein

Examples of complete protein in the following topics:

• Mapping Protein-Protein Interactions

  • Mapping protein-protein interactions gives us a better understanding of molecular mechanisms inside the cell.
  • The protein complexes formed could be stable (proteins interact for a prolonged period of time) or transient (proteins interact for a brief period of time).
  • The complete map of protein interactions that can occur in a living organism is called the interactome.
  • The tag serves as a tool to purify the bait protein and associated proteins by affinity chromatography.
  • Principle of the bait and prey method for the study of protein-protein interaction.

• Protease Inhibitors

  • Protease inhibitors target viral proteases which are key enzymes for the completion of viral maturation.
  • Proteases are enzymes that have the ability to cut proteins into peptides.
  • They are used by some viruses (e.g., HIV) to cleave precursor long protein chains into individual proteins.
  • This allows the completion of the assembly step in the viral life cycle where the proteins and the viral RNA come together to form virion particles ready to exit the cell.
  • This leads to a lack of cleavage of the polypeptide chains of two crucial viral proteins, Gag and Pol, which are essential structural and enzymatic proteins of HIV.

• Crystallographic Analysis

  • Electron crystallography has been used to determine some protein structures, most notably membrane proteins and viral capsids.
  • Studies of protein crystallography help determine the three dimensional structure of proteins and analyze their function alone or within multimolecular assemblies.
  • The structure-function analysis is completed by biochemical and biophysical studies in solution.
  • The protocol for completing a successful crystallographic analysis requires production of proteins (cloning, mutagenesis, bacterial culture, etc.), purification of recombinant proteins (such as chromatography of affinity and gel filtration), enzymatic tests and inhibition measurement (spectrophotometry), crystallization, x-rays crystallography and structural analysis, interactions determination (microcalorimetry, fluorescence, BIAcore), conformational analyses (circular dichroism, ultracentrifugation, light scattering), modifications analysis (mass spectrometry), bioinformatics, and molecular modelisation.
  • The Protein Data Bank (PDB) is a freely accessible repository documenting the structures of proteins and other biological macromolecules.

• Nature of the Virion

  • A virion is a complete viral particle consisting of RNA or DNA surrounded by a protein shell, constituting the infective form of a virus.
  • Virion capsids are formed from identical protein subunits called capsomeres.
  • Virally coded protein subunits will self-assemble to form a capsid, in general requiring the presence of the virus genome.
  • Complex viruses code for proteins that assist in the construction of their capsid.
  • Proteins associated with nucleic acid are known as nucleoproteins, and the association of viral capsid proteins with viral nucleic acid is called a nucleocapsid.

• General Morphology

  • A complete virus particle, known as a virion, consists of nucleic acid surrounded by a protective coat of protein called a capsid.
  • These are formed from identical protein subunits called capsomeres.
  • Virally coded protein subunits will self-assemble to form a capsid, in general requiring the presence of the virus genome.
  • Complex viruses code for proteins that assist in the construction of their capsid.
  • Proteins associated with nucleic acid are known as nucleoproteins, and the association of viral capsid proteins with viral nucleic acid is called a nucleocapsid.

• Archaeoglobus

  • This is supported by the presence of 10 conserved signature proteins that are uniquely found in all methanogens and Archaeoglobus.
  • However, the possibility that the shared presence of these signature proteins in these archaeal lineages is due to lateral gene transfer cannot be excluded.
  • The complete genome sequence from Archaeoglobus fulgidus reveals the presence of a complete set of genes for methanogenesis.
  • Another quarter encodes proteins unique to the archaeal domain.
  • One observation about the genome is that there are many gene duplications and the duplicated proteins are not identical.

• Ribosomes

  • The purpose of the ribosome is to translate messenger RNA (mRNA) into proteins with the aid of tRNA.
  • Ribosomes are tiny spherical organelles that make proteins by joining amino acids together.
  • Proteins synthesized in each of these locations serve a different role in the cell.
  • To complete the mechanism of ribosome assembly, these precursor rRNA gets transformed in the polysomes.
  • The ribosome assembles amino acids into a protein.

• Cofactors and Energy Transitions

  • A cofactor is a non-protein chemical compound that is bound to a protein and is required for the protein's biological activity.
  • A cofactor is a non-protein chemical compound that is bound to a protein and is required for the protein's biological activity.
  • These proteins are commonly enzymes.
  • An inactive enzyme without the cofactor is called an apoenzyme, while the complete enzyme with cofactor is the holoenzyme.
  • The term is used in other areas of biology to refer more broadly to non-protein (or even protein) molecules that either activate, inhibit, or are required for the protein to function.

• Diverse Cell Forms of Methanogens

  • There are over 50 described species of methanogens, sharing over 30 signature proteins.
  • There are over 50 described species of methanogens, sharing over 30 signature proteins.
  • Therefore, the large numbers of proteins uniquely shared by all methanogens may be due to lateral gene transfers.
  • Those that do not contain pseudopeptidoglycan have at least one paracrystalline array (S-layer) made up of proteins that fit together like a jigsaw puzzle.
  • It was the first archaeon to have its complete genome sequenced, identifying many genes and synthesis pathways unique to the archaea.

• Repression of Anabolic Pathways

  • Regulatory protein is a term used in genetics to describe a protein involved in regulating gene expression.
  • Such proteins are usually bound to a DNA binding site which is sometimes located near the promoter although this is not always the case.
  • Sites of DNA sequences where regulatory proteins bind are called enhancer sequences.
  • Activators bind to the upstream portion of the promoter, such as the CAP region (completely upstream from the transcript).
  • In bacteria, the lac repressor protein blocks the synthesis of enzymes that digest lactose when there is no lactose to feed on.