Studies on protein-based microcompartment (encapsulin) from Rhodococcus erythropolis N771

2015 Fiscal Year Final Research Report

• Project/Area Number: 25440015
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Structural biochemistry
• Research Institution: Tokyo University of Agriculture and Technology
• Principal Investigator: Noguchi Keiichi 東京農工大学, 学術研究支援総合センター, 准教授 (00251588)
• Co-Investigator(Renkei-kenkyūsha): YOHDA Masafumi 東京農工大学, 大学院工学研究院, 教授 (50250105)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: ナノ構造体 / Ｘ線回折 / 結晶構造 / ナノ粒子 / タンパク質シェル構造体 / ウィルス様粒子 / 認識配列

Outline of Final Research Achievements

The encapsulin nanocompartment from Rhodococcus erythropolis N771 was expressed and purified in wild-type and C-terminally His-tagged forms. Negative-stained transmission electron microscopy　observation showed that the encapsulin monomers were assembled as a spherical particle with a diameter of 28 nm. Heterogeneous guest proteins such as enhanced green fluorescence protein and firefly luciferase were packaged into the internal cavity of the encapsulin nanocompartment by fusing the C-terminal 37-amino-acid sequence of the R. erythropolis N771 DypB peroxidase to the C-terminus. Two kinds of crystallization conditions were found for the recombinant protein. Crystals obtained using one of two conditions diffracted to 3.3Å resolution and the crystal system is trigonal, with unit-cell parameters of a = 235.5Å and α = 63.2°. A self-rotation function calculated using the collected data suggested presence of 2-, 3- and 5-fold axes in the asymmetric unit.

Free Research Field

構造生物学