Novel and essential molecular chaperone systems in cyanobacteria

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K05407
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 38020:Applied microbiology-related
• Research Institution: Saitama University
• Principal Investigator: Nakamoto Hitoshi 埼玉大学, 理工学研究科, 教授 (30192678)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 分子シャペロン / 熱ショックタンパク質 / シャペロンネットワーク / シアノバクテリア / ClpB / DnaK / GroEL / DnaJ

Outline of Final Research Achievements

In contrast to E.coli, cyanobacteria including Synechococcus elongatus PCC7942 contain multiple homologs (paralogs) of groEL and clpB. One of the clpB genes (clpB2) is the only example of clpB/hsp104 which is essential. E.coli has multiple dnaK genes which are not essential whereas some dnaK genes in the family are essential in cyanobacteria. DnaK functions as a central hub in the cellular molecular chaperone network. It cooperates with other molecular chaperones such as ClpB. In the present study, I focused upon unique chaperone paralogs and essential dnaK and clpB genes in S. elongatus PCC7942. As far as I know, there is no study on essential DnaK and ClpB. We established chaperone systems which consist of essential DnaK2, DnaJ1/DnaJ2, and ClpB2.

Free Research Field

生化学

Academic Significance and Societal Importance of the Research Achievements

DnaKやClpBなどの分子シャペロン（系）の研究は、主に大腸菌の（非必須）分子シャペロンやコシャペロンに関して行われてきた。本研究では、大腸菌のホモログとは生理的機能や生化学的特性が異なる（今までに研究対象とはならなかった）ホモログ（パラログ）を解析することで独自性・新規性の高い研究を行うことができた。これらの成果は、高等植物などの独立栄養生物の分子シャペロン研究に資するものと考える。