Molecular analysis of cyclic α-maltosyl-(1→6)-maltose binding protein in the bacterial metabolic pathway

Masaki Kohno; Takatoshi Arakawa; Naoki Sunagawa; Tetsuya Mori; Kiyohiko Igarashi; Tomoyuki Nishimoto; Shinya Fushinobu

doi:10.1371/journal.pone.0241912

Molecular analysis of cyclic α-maltosyl-(1→6)-maltose binding protein in the bacterial metabolic pathway

PLoS One. 2020 Nov 19;15(11):e0241912. doi: 10.1371/journal.pone.0241912. eCollection 2020.

Authors

Masaki Kohno^{1

2}, Takatoshi Arakawa^{1

3}, Naoki Sunagawa⁴, Tetsuya Mori², Kiyohiko Igarashi^{4

5}, Tomoyuki Nishimoto², Shinya Fushinobu^{1

3}

Affiliations

¹ Department of Biotechnology, The University of Tokyo, Tokyo, Japan.
² R&D Division, HAYASHIBARA CO., LTD., Okayama, Japan.
³ Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Tokyo, Japan.
⁴ Department of Biomaterial Sciences, The University of Tokyo, Tokyo, Japan.
⁵ VTT Technical Research Centre of Finland Ltd., Espoo, Finland.

Abstract

Cyclic α-maltosyl-(1→6)-maltose (CMM) is a cyclic glucotetrasaccharide with alternating α-1,4 and α-1,6 linkages. Here, we report functional and structural analyses on CMM-binding protein (CMMBP), which is a substrate-binding protein (SBP) of an ABC importer system of the bacteria Arthrobacter globiformis. Isothermal titration calorimetry analysis revealed that CMMBP specifically bound to CMM with a Kd value of 9.6 nM. The crystal structure of CMMBP was determined at a resolution of 1.47 Å, and a panose molecule was bound in a cleft between two domains. To delineate its structural features, the crystal structure of CMMBP was compared with other SBPs specific for carbohydrates, such as cyclic α-nigerosyl-(1→6)-nigerose and cyclodextrins. These results indicate that A. globiformis has a unique metabolic pathway specialized for CMM.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Arthrobacter / metabolism*
Calorimetry
Crystallography, X-Ray
Cyclodextrins / metabolism
Disaccharides / metabolism
Maltose-Binding Proteins / chemistry*
Maltose-Binding Proteins / metabolism*
Metabolic Networks and Pathways
Models, Molecular
Protein Conformation
Protein Domains

Substances

Cyclodextrins
Disaccharides
Maltose-Binding Proteins
laminaribiose

Supplementary concepts

Arthrobacter globiformis

Grants and funding

This study was partially supported by JSPS-KAKENHI (15H02443, 26660083, and 24380053 to S. F.; and 15H04526, 18H02252 and 19H03013 to K. I.), a Grant-in-Aid for Innovative Areas from the Japanese Ministry of Education, Culture, Sports, and Technology (MEXT) (No. 18H05494 to K.I.), and Platform Project for Supporting Drug Discovery and Life Science Research (Basis for Supporting Innovative Drug Discovery and Life Science Research (BINDS)) from the Japanese Ministry of Education, Culture, Sports, and Technology (MEXT). Hayashibara Co. Ltd. provided support in the form of salaries three authors (MK, TM,TN), but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the `author contributions’ section.