8H17

Crystal structure of the Globin domain of Thermosynechococcus elongatus BP-1

8H17 の概要

• エントリーDOI: 10.2210/pdb8h17/pdb
• 分子名称: Tlr1989 protein, IMIDAZOLE, PROTOPORPHYRIN IX CONTAINING FE, ... (4 entities in total)
• 機能のキーワード: thermosynechococcus vestitus bp-1, haemoglobin, imidazole, penta-cordinated heme, heme binding, iron, thermophile, cyanobacteria, synechococcus, oxygen binding
• 由来する生物種: Thermosynechococcus vestitus BP-1
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 23529.91

構造登録者

Mathur, S.,Yadav, S.K.,Pal, K.R.,Kundu, S. (登録日: 2022-09-30, 公開日: 2023-04-26, 最終更新日: 2024-05-01)

主引用文献

Mathur, S.,Yadav, S.K.,Yadav, K.,Bhatt, S.,Kundu, S.
A novel single sensor hemoglobin domain from the thermophilic cyanobacteria Thermosynechococcus elongatus BP-1 exhibits higher pH but lower thermal stability compared to globins from mesophilic organisms.
Int.J.Biol.Macromol., 240:124471-124471, 2023

PubMed Abstract: Thermosynechococcus elongatus-BP1 belongs to the class of photoautotrophic cyanobacterial organisms. The presence of chlorophyll a, carotenoids, and phycocyanobilin are the characteristics that categorize T. elongatus as a photosynthetic organism. Here, we report the structural and spectroscopic characteristics of a novel hemoglobin (Hb) Synel Hb from T.elongatus, synonymous with Thermosynechococcus vestitus BP-1. The X-ray crystal structure (2.15 Å) of Synel Hb suggests the presence of a globin domain with a pre-A helix similar to the sensor domain (S) family of Hbs. The rich hydrophobic core accommodates heme in a penta-coordinated state and readily binds an extraneous ligand (imidazole). The absorption and circular dichroic spectral analysis of Synel Hb reiterated that the heme is in Fe state with a predominantly α-helical structure similar to myoglobin. Synel Hb displays higher resistance to structural perturbations induced via external stresses like pH and guanidium hydrochloride, which is comparable to Synechocystis Hb. However, Synel Hb exhibited lower thermal stability compared to mesophilic hemoglobins. Overall, the data is suggestive of the structural sturdiness of Synel Hb, which probably corroborates its origin in extreme thermophilic conditions. The stable globin provides scope for further investigation and may lead to new insights with possibilities for engineering stability in hemoglobin-based oxygen carriers.

PubMed: 37076076
DOI: 10.1016/j.ijbiomac.2023.124471

実験手法

X-RAY DIFFRACTION (2.15 Å)