cofactor

Examples of cofactor in the following topics:

• Cofactors and Energy Transitions

  • Cofactors are either organic or inorganic.
  • An inactive enzyme without the cofactor is called an apoenzyme, while the complete enzyme with cofactor is the holoenzyme.
  • Some enzymes or enzyme complexes require several cofactors.
  • Organic cofactors are often vitamins or are made from vitamins.
  • Cofactors can be divided into two broad groups: organic cofactors, such as flavin or heme, and inorganic cofactors, such as the metal ions Mg2+, Cu+, Mn2+, or iron-sulfur clusters.

• Nanoarchaeum and Aciduliprofundum

  • N. equitans genome consists of a single circular chromosome, and lacks almost all genes required for synthesis of amino acids, nucleotides, cofactors, and lipids, but encodes everything needed for repair and replication. 95% of its DNA encodes for proteins for stable RNA molecules.
  • Nanoarchaeum cannot synthesize most nucleotides, amino acids, lipids, and cofactors.

• Iron-Binding Proteins

  • They are carrier proteins (those used to move ions and molecules across membranes) and more generally metalloproteins (those which contain a metal ion cofactor).

• Gene Inversion

  • For this to occur, there is typically one or more cofactors (to name a few: DNA-binding proteins and the presence or absence of DNA binding sites) and a site specific recombinase.

• Nitrogenase and Nitrogen Fixation

  • All nitrogenases have an iron- and sulfur-containing cofactor that includes a heterometal complex in the active site (e.g., FeMoCo).

• Regulation of Sigma Factor Translation

  • The regulation of expression of sigma factors occurs at transcriptional, translational, and post-translational levels as dictated by the cellular environment and the presence or absence of numerous cofactors.

• Biosynthesis and Energy

  • Biosynthetic building blocks utilized by organisms include amino acids, purines, pyrimidines, lipids, sugars, and enzyme cofactors.

• Nitrogen Fixation Mechanism

  • Component I known as MoFe protein or nitrogenase contains 2 Mo atoms, 28 to 34 Fe atoms, and 26 to 28 acid-labile sulfides, also known as a iron-molybdenum cofactor (FeMoco).
  • C) Electrons are further shuttled to the iron-molybdenum cofactor (FeMoco), and ATP is hydrolised to ADP.

• Oxidoreductase Protein Complexes

  • This group of enzymes usually utilizes NADP or NAD+ as cofactors.

• Anaerobiosis and N2 Fixation

  • Due to the oxidation carried out by oxygen, most nitrogenases, which are essential large reduction complexes are irreversibly inhibited by O2, which degradatively oxidizes the Fe-S cofactors.