约翰斯敦血红蛋白[β109（G11）缬氨酸→亮氨酸]：一种导致红细胞增多症的新型电泳沉默变异体。

Hb Johnstown [beta 109 (G11) Val----Leu]: a new electrophoretically silent variant that causes erythrocytosis.

作者信息

Jones R T, Saiontz H I, Head C, Shih D T, Fairbanks V F

机构信息

Department of Biochemistry and Molecular Biology, Oregon Health Sciences University, Portland 97201.

出版信息

Hemoglobin. 1990;14(2):147-56. doi: 10.3109/03630269009046956.

DOI:10.3109/03630269009046956

PMID:2272838

Abstract

A high oxygen affinity hemoglobin, previously undescribed, was found in a healthy, asymptomatic patient with mild erythrocytosis and left-shifted hemoglobin-O2 dissociation curve. The hemoglobin variant could not be distinguished from Hb A by any of several electrophoretic methods nor by ion exchange chromatography. It was separated and analyzed by reversed phase high performance liquid chromatography. Structural analysis revealed the substitution beta 109 (G11) Val----Leu. The variant was named Hb Johnstown. The amino acid substitution perhaps disrupts alpha 1 beta 1 contacts in the deoxyhemoglobin conformation, thus shifting the equilibrium towards the high affinity oxyhemoglobin conformation.

摘要

在一名患有轻度红细胞增多症且血红蛋白 - O₂解离曲线左移的健康无症状患者中，发现了一种此前未被描述过的高氧亲和力血红蛋白。通过几种电泳方法以及离子交换色谱法，均无法将该血红蛋白变体与Hb A区分开来。它是通过反相高效液相色谱法分离和分析的。结构分析显示存在β109（G11）缬氨酸→亮氨酸的替换。该变体被命名为Hb约翰斯敦。这种氨基酸替换可能破坏了脱氧血红蛋白构象中的α1β1接触，从而使平衡向高亲和力氧合血红蛋白构象偏移。