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The ALDH2 gene is about 44 kbp in length and contains at least 13 exons which encode 517 amino acid residues. Except for the signal NH2-terminal peptide, which is absent in the mature enzyme, the amino acid sequence deduced from the exons coincided with the reported primary structure of human liver ALDH2.
ALDH2, which has a lower K M for acetaldehydes than ALDH1 and acts predominantly in the mitochondrial matrix, is the main enzyme in acetaldehyde metabolism and has three genotypes. A single point mutation (G → A) at exon 12 of the ALDH2 gene causes a replacement of glutamate with lysine at residue 487, resulting in the ALDH2K enzyme. [8]
Aldehyde dehydrogenase is a polymorphic enzyme [3] responsible for the oxidation of aldehydes to carboxylic acids. [3] There are three different classes of these enzymes in mammals: class 1 (low K m, cytosolic), class 2 (low K m, mitochondrial), and class 3 (high K m, such as those expressed in tumors, stomach, and cornea).
People have various ALDH2 alleles. ALDH2*1 is a common allele , but about 40% of people of East Asian ethnicity have one or two copies of the dominant ALDH2*2 instead, which causes ALDH2 deficiency. If deficient people drink ethanol, they suffer from alcohol flush reaction due to acetaldehyde accumulation. [3] Four Alda-1 molecules bind to each ...
This also limits the number of electrons in the same orbital to two. The pairing of spins is often energetically favorable, and electron pairs therefore play a large role in chemistry. They can form a chemical bond between two atoms, or they can occur as a lone pair of valence electrons. They also fill the core levels of an atom.
In organic chemistry, neighbouring group participation (NGP, also known as anchimeric assistance) has been defined by the International Union of Pure and Applied Chemistry (IUPAC) as the interaction of a reaction centre with a lone pair of electrons in an atom or the electrons present in a sigma or pi bond contained within the parent molecule but not conjugated with the reaction centre.
Additionally exons can be classified into nine different groups based on the phase of the flanking introns (symmetrical: 0-0, 1-1, 2-2 and asymmetrical: 0–1, 0–2, 1–0, 1–2, etc.) Symmetric exons are the only ones that can be inserted into introns, undergo duplication, or be deleted without changing the reading frame. [2]
neutral counting: Ti contributes 4 electrons, each chlorine radical contributes one each: 4 + 4 × 1 = 8 valence electrons ionic counting: Ti 4+ contributes 0 electrons, each chloride anion contributes two each: 0 + 4 × 2 = 8 valence electrons conclusion: Having only 8e (vs. 18 possible), we can anticipate that TiCl 4 will be a good Lewis acid ...