4EUK:
reference: Structure-Function Analysis of Arabidopsis thaliana Histidine Kinase AHK5 Bound to Its Cognate Phosphotransfer Protein AHP1., Bauer J, Reiss K, Veerabagu M, Heunemann M, Harter K, Stehle T, Mol Plant. 2013 Jan 24. PMID: 23132142

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