5VIK:
reference: Designing brighter near-infrared fluorescent proteins: insights from structural and biochemical studies., Baloban M, Shcherbakova DM, Pletnev S, Pletnev VZ, Lagarias JC, Verkhusha VV, Chem Sci. 2017 Jun 1;8(6):4546-4557. doi: 10.1039/c7sc00855d. Epub 2017 May 4. PMID: 28936332

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