Instruct: Identify the main category of Biorxiv papers based on the titles and abstracts
Query: The tetrameric assembly of 2-aminomuconic acid dehydrogenase is a functional requirement of cofactor NAD+ binding The bacterium Pseudomonas sp. AP-3 is able to use the environmental pollutant 2-aminophenol as its sole source of carbon, nitrogen, and energy. Eight genes (amnA, B, C, D, E, F, G, and H) encoding 2-aminophenol metabolizing enzymes are clustered into a single operon. 2-aminomuconic 6-semialdehyde dehydrogenase (AmnC), a member of the aldehyde dehydrogenase (ALDH) superfamily, is responsible for oxidizing 2-aminomuconic 6-semialdehyde to 2-aminomuconate. In contrast to many other members of the ALDH superfamily, the structural basis of the catalytic activity of AmnC remains elusive. Here, we present the crystal structure of AmnC, which displays a homotetrameric quaternary assembly that is directly involved in its enzymatic activity. The tetrameric state of AmnC in solution was also presented using small-angle X-ray scattering. The tetramerization of AmnC is mediated by the assembly of a protruding hydrophobic beta-strand motif and residues V121 and S123 located in the NAD+-binding domain of each subunit. Dimeric mutants of AmnC dramatically lose NAD+ binding affinity and enzyme activity, indicating that tetrameric assembly of AmnC is required for oxidizing the unstable metabolic intermediate 2-aminomuconic 6-semialdehyde to 2-aminomuconic acid in the 2-aminophenol metabolism pathway.
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The categories of this paper are: neuroscience
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The categories of this paper are: immunology
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The categories of this paper are: paleontology
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The categories of this paper are: developmental
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The categories of this paper are: cancer
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The categories of this paper are: cell
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The categories of this paper are: toxicology
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The categories of this paper are: pathology
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The categories of this paper are: synthetic
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The categories of this paper are: and
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The categories of this paper are: biophysics
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The categories of this paper are: molecular
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The categories of this paper are: physiology
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The categories of this paper are: systems
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The categories of this paper are: bioinformatics
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The categories of this paper are: zoology