US 12,436,104 B2
Fluorescent probe for branched chain amino acids and use thereof
Yi Yang, Shanghai (CN); Yuzheng Zhao, Shanghai (CN); Xie Li, Shanghai (CN); Yejun Zou, Shanghai (CN); and Changcheng Zhang, Shanghai (CN)
Assigned to East China University of Science and Technology, Shanghai (CN)
Appl. No. 16/981,088
Filed by East China University of Science and Technology, Shanghai (CN)
PCT Filed Mar. 15, 2019, PCT No. PCT/CN2019/078274
§ 371(c)(1), (2) Date Apr. 29, 2021,
PCT Pub. No. WO2019/174633, PCT Pub. Date Sep. 19, 2019.
Claims priority of application No. 201810215698.7 (CN), filed on Mar. 15, 2018.
Prior Publication US 2024/0027344 A1, Jan. 25, 2024
Int. Cl. A61K 38/00 (2006.01); G01N 21/64 (2006.01)
CPC G01N 21/6428 (2013.01) 10 Claims
 
1. A fluorescent sensor, comprising
a) a leucine responsive polypeptide, and
b) an optically active polypeptide,
wherein the optically active polypeptide is a fluorescent protein or a functional fragment thereof,
wherein the optically active polypeptide is inserted in the leucine responsive polypeptide,
and wherein the leucine responsive polypeptide has a sequence shown in SEQ ID NO: 1, or a sequence having at least 90% identity with SEQ ID NO: 1 and having a structure in which typical α/β globular domains of a periplasm binding protein are engaged with a hinge, and the optically active polypeptide is inserted in the leucine responsive polypeptide at a site selected from the group consisting of: 251/255, 325/326, 325/327, 325/328, 325/329, 326/327, 326/328, 326/329, and 327/328, or
the leucine responsive polypeptide has a sequence shown in SEQ ID NO: 2, or a sequence having at least 90% identity with SEQ ID NO: 2 and having a structure in which typical α/β globular domains of a periplasm binding protein are engaged with a hinge, and the optically active polypeptide is inserted in the leucine responsive polypeptide at a site selected from the group consisting of: 328/329, 328/330, and 329/330.