2NVJ:
reference: Segment TM7 from the cytoplasmic hemi-channel from V(O)-H(+)-V-ATPase includes a flexible region that has a potential role in proton translocation., Duarte AM, de Jong ER, Wechselberger R, van Mierlo CP, Hemminga MA, Biochim Biophys Acta. 2007 Sep;1768(9):2263-70. Epub 2007 May 21. PMID: 17573038

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