8WB2

Heme-bound Arabidopsis thaliana temperature-induced lipocalin

Summary for 8WB2

• Entry DOI: 10.2210/pdb8wb2/pdb
• Descriptor: Temperature-induced lipocalin-1, PROTOPORPHYRIN IX CONTAINING FE (3 entities in total)
• Functional Keywords: heme, arabidopsis thaliana, lipocalin, plant protein
• Biological source: Arabidopsis thaliana (thale cress)
• Total number of polymer chains: 1
• Total formula weight: 24305.10

Authors

Dong, C.,Liu, L. (deposition date: 2023-09-08, release date: 2023-12-27, Last modification date: 2024-01-03)

Primary citation

Dong, C.S.,Zhang, W.L.,Wang, X.Y.,Wang, X.,Wang, J.,Wang, M.,Fang, Y.,Liu, L.
Crystallographic and functional studies of a plant temperature-induced lipocalin.
Biochim Biophys Acta Gen Subj, 1868:130540-130540, 2023

PubMed Abstract: Arabidopsis thaliana temperature-induced lipocalin (AtTIL) is a prototypical member of plant lipocalins and participates in a variety of cellular processes, particularly stress responses. Bioinformatical and physiological studies have proposed its promiscuous ligand-binding ability, but the molecular basis is yet unclear. Here, we report the 1.9-Å crystal structure of AtTIL in complex with heme. Spectrophotometric absorbance titration with heme yields a dissociation constant of ∼2 micromolar, indicating the relatively weak interaction between AtTIL and heme, which is confirmed by the AtTIL-heme structure. Although binding to retinal or biliverdin is not detected, such possibility can not be precluded as suggested by comparison with other lipocalin structures. These results show that AtTIL is a structural and functional homolog of the bacterial lipocalin Blc.

PubMed: 38103756
DOI: 10.1016/j.bbagen.2023.130540

Experimental method

X-RAY DIFFRACTION (1.9 Å)