Protein-Based Microtubes and Nanotubes as Ultrasmall Biomaterials

Cylindrical hollow structures in micro/nanometer-scale prepared using biomacromolecules, such as proteins, peptides, DNAs, and polysaccharides, have attracted considerable attentions because of their potential applications. In this seminar, I would like to highlight the latest results from my research on protein-based smart microtubes (MTs) and nanotubes (NTs) as ultrasmall biomaterials.
These practical cylinders were prepared using an alternate layer-by-layer assembly of proteins and oppositely charged poly(amino acids) into a track-etched porous polycarbonate (PC) membrane with the subsequent dissolution of the template^.1 The multilayered tube structure resembles a rolled sandwich. Various functionalities can be introduced into the inner surface, cylindrical wall, and outer surface (Figure 1).² The inner surface-modified NTs can capture nanoparticles (NPs),1 viruses,³ and bacteria in capillaries⁴  The tubules containing enzymes and AuNPs in stratiform walls act as microreactors.⁵  Moreover, MTs with PtNPs or catalase as an interior surface are self-propelled in an aqueous H₂O₂ solution by jetting O₂ bubbles from the open-end terminus.^6,7  These swimming tubes efficiently captured E. coli. like a micromop. Avidin-coated MT motors caught biotinylated particles.^8,9 Enzyme-coated swimming tubes accelerated catalytic reaction by their stirring motion.
New polymer-based MT motors prepared by photopolymerization in the PC template are also described.

Figure 1. Schematic illustrations of protein-based micro/nanotubes and optical microscopic observation of
swimming catalase microtube in water.

References
1) X. Qu, T. Komatsu, ACS Nano 2010, 4, 563.
2) T. Komatsu, Chem. Lett. 2020, 49, 1245. (Review, Cover Image)
3) T. Komatsu, X. Qu, H. Ihara, M. Fujihara, H. Azuma, H. Ikeda, J. Am. Chem. Soc. 2011, 133, 3246.
4) S. Yuge, M. Akiyama, T. Komatsu, Chem. Commun. 2014, 50, 9640. (Cover Image)
5) R. Adachi, M. Akiyama, Y. Morita, T. Komatsu, Chem. Asian J. 2018, 13, 2796.
6) S. Kobayakawa, Y. Nakai, M. Akiyama, T. Komatsu, Chem. Eur. J. 2017, 23, 5044. (Cover Image)
7) N. Sugai, Y. Nakai, Y. Morita, T. Komatsu, ACS Appl. Nano Mater. 2018, 1, 3080. (Cover Image)
8) Y. Nakai, N. Sugai, H. Kusano, Y. Morita, T. Komatsu, ACS Appl. Nano Mater. 2019, 2, 4891. (Cover Image)
9) M. Umebara, N. Sugai, K. Murayama, T. Sugawara, Y. Akashi, Y. Morita, K. Kato, T. Komatsu, Mater. Adv.
2021, 2, 6428.

BIOGRAPHY

Teruyuki Komatsu received his Ph.D. in 1994 from Waseda University (Tokyo, Japan) on the synthesis of iron-porphyrin derivatives and their oxygen coordination. After postdoctoral study with Jürgen-Hinrich Fuhrhop at Freie Universität Berlin (1995‒1997) to work on supramolecular assemblies of amphiphilic porphyrins, he returned to Waseda University, where he was appointed as a Lecturer and was promoted to Associate Professor in 2003. From 2006 to 2010, he held additional post of a PRESTO researcher of Japan Science and Technology Agency (JST) and started protein nanotube chemistry. In 2010, he moved to Chuo University (Tokyo) as a full professor of Department of Applied Chemistry. His current research interests are the synthesis and development of smart biomaterials and their practical applications, mainly protein micro/nanotube motors and hemoglobin-based oxygen carriers (artificial blood).

Prof. Teruyuki Komatsu
Department of Applied Chemistry, Faculty of Science and Engineering,
Chuo University
komatsu@kc.chuo-u.ac.jp