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    Table of contents
    1. 1. Protein Summary
    2. 2. Ligand Summary

    Title Crystal structure of Putative reductase (NP_038806.2) from MUS MUSCULUS at 1.18 A resolution. To be published
    Site JCSG
    PDB Id 3ln3 Target Id 400045
    Molecular Characteristics
    Source Mus musculus
    Alias Ids TPS30603,NP_038806.2, _0087.001827_, 326044 Molecular Weight 37041.85 Da.
    Residues 323 Isoelectric Point 6.67
    Sequence msskqhcvklndghlipalgfgtykpkevpksksleaaclaldvgyrhvdtayayqveeeigqaiqski kagvvkredlfvttklwctcfrpelvkpalekslkklqldyvdlyimhypvpmksgdndfpvneqgksl ldtvdfcdtwerleeckdaglvksigvsnfnhrqlerilnkpglkykpvcnqvechlylnqrklldyce skdivlvaygalgtqrykewvdqnspvllndpvlcdvakknkrspalialryliqrgivplaqsfkene mrenlqvfgfqlspedmktldglnknfrylpaeflvdhpeypfveey
      BLAST   FFAS

    Structure Determination
    Method XRAY Chains 1
    Resolution (Å) 1.18 Rfree 0.156
    Matthews' coefficent 2.29 Rfactor 0.131
    Waters 405 Solvent Content 46.17

    Ligand Information


    Google Scholar output for 3ln3
    1. Characterizing Protein Shape by a Volume Distribution Asymmetry Index
    N Arrigo, P Paci, L Di Paola, D Santoni - Open Bioinformatics , 2012 - benthamscience.com

    Protein Summary

    Structural basis for cofactor selectivity from the crystal structure of the mouse AKR1C13: NAD complex at  1.18Å resolution

    This mouse protein is annotated as an AKR1C13 (aldo-keto reductase family 1, member C13) belonging to the aldo/keto reductase family PF00248 in Pfam. This is the first crystal structure of an AKR1C13 protein, although many crystal structures of other proteins have been solved from this protein family.


    The protein was subjected to reductive methylation after purification to facilitate crystallization and the modified residues are shown in sticks in the figure.

    Endogenous NAD was modeled at the putative active site. This finding supports  a biochemical study showing that AKR1C13 prefers NAD for function over NADP, as opposed to other related aldo-keto reductases (AKRs). The structure of this complex thus reveals the structural basis for this cofactor preference and selectivity.

     In addition, MPD (2,4-methylpentanediol) was found in the structure near the NAD and was modeled as MPD but it could be some other similar compound too. Interestingly, some of the other related crystal structures have bound MPD, but in those cases, the MPD is from the crystallization condition.

    It is likely that this bound MPD may mimic natural substrate since the expected ligands for AKR1C13 are non-steroidal alcohols (like s-tetralol, geraniol and farnesol), which are smaller than the steroidal alcohols that are the substrates for other AKRs.

    A comparison of the residues involved in interactions with NAD and MPD and critical residues in the other AKRs will be provided later along with some analysis how these different family members may have evolved. A more thorough analysis is in progress.



    1)Characterization of rat and mouse NAD+-dependent 3alpha/17beta/20alpha-hydroxysteroid dehydrogenases and identification of substrate specificity determinants by site-directed mutagenesis. Endo S, Sanai M, Horie K, Matsunaga T, Ishikura S, Tajima K, El-Kabbani O, Hara A. Arch Biochem Biophys. 2007 Nov 1;467(1):76-86. Epub 2007 Aug 24.PMID: 17888864

    2)Cloning and characterization of two novel aldo-keto reductases (AKR1C12 and AKR1C13) from mouse stomach. Ikeda S, Okuda-Ashitaka E, Masu Y, Suzuki T, Watanabe K, Nakao M, Shingu K, Ito S. FEBS Lett. 1999 Oct 15;459(3):433-7.PMID: 10526179

    Ligand Summary




    No references found.

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