Patent ID: 8846365
Filing Date: 2014-09-30
Classification: C07K

Abstract:
1. An isolated nucleic acid which encodes a phosphate fluorescent indicator comprising: a phosphate binding protein moiety polypeptide from a type II phosphate periplasmic binding protein comprising a first and a second globular domain separated by a hinge, the phosphate binding moiety having at least 95% identity to the amino acid sequence as set forth in SEQ ID NO: 4 and wherein the first globular domain comprises the amino and carboxyl termini of the phosphate binding protein moiety; a donor fluorescent protein moiety fused to the amino terminus of the phosphate binding protein moiety; and an acceptor fluorescent protein moiety fused to the carboxyl terminus of the phosphate binding protein moiety; wherein fluorescence resonance energy transfer (FRET) between the donor moiety and the acceptor moiety is altered when the donor moiety is excited and phosphate binds to the phosphate binding protein moiety.