scispace - formally typeset
Search or ask a question
Author

Tsuneyoshi Matsuoka

Bio: Tsuneyoshi Matsuoka is an academic researcher from Toyohashi University of Technology. The author has contributed to research in topics: Flame spread & Combustion. The author has an hindex of 8, co-authored 41 publications receiving 269 citations. Previous affiliations of Tsuneyoshi Matsuoka include Applied Science Private University & Hokkaido University.

Papers
More filters
Journal ArticleDOI
TL;DR: A novel strategy for the regulation and preservation of the enzymatic activity even after heat treatment by the complex formation with a cationic smart copolymer, poly(N,N-diethylaminoethyl methacrylate)-graft-poly(ethylene glycol) (PEAMA-g-PEG).
Abstract: Proteins have evolved to acquire highly specialized biological functions and are ideal for various applications in both medicine and biotechnology, although denaturation is one of the major problems in protein chemistry. Here, we show a novel strategy for the regulation and preservation of the enzymatic activity even after heat treatment by the complex formation with a cationic smart copolymer, poly(N,N-diethylaminoethyl methacrylate)-graft-poly(ethylene glycol) (PEAMA-g-PEG). PEAMA-g-PEG suppressed the enzymatic activity of lysozyme completely without any conformational change, indicating complex formation and the capping of the active site of lysozyme by PEAMA-g-PEG. The addition of an anionic polymer, poly(acrylic acid) (PAAc), recovered the inhibited enzymatic activity of the lysozyme/PEAMA-g-PEG complex completely. Surprisingly, even after heating the lysozyme with PEAMA-g-PEG for 20 min at 98 degrees C, the addition of PAAc recovered 80% enzymatic activity of lysozyme. Circular dichroism (CD) spectral analysis clearly indicated that the irreversible inactivation of lysozyme induced by the heat treatment was suppressed by the complex formation with PEAMA-g-PEG.

57 citations

Journal ArticleDOI
TL;DR: Comparison of heat treatment of native lysozyme and oxidative refolding from the reduced and denatured state of lyso enzyme in the presence of 44 different additives revealed an indispensable chemical structure for the additives to be effective against heat‐induced misfolding and for refolding.
Abstract: This article investigates solution additives that prevent misfolding of lysozyme from heating treatment and during refolding processes. Comparison of heat treatment of native lysozyme and oxidative refolding from the reduced and denatured state of lysozyme in the presence of 44 different additives revealed an indispensable chemical structure for the additives to be effective against heat-induced misfolding and for refolding. The additives effective against heat treatment of native lysozyme possessed a main chain of the amino acid moiety. Amino acids that have esterificated and amidated carboxy groups prevented heat-induced misfoldings more effectively than amino acids themselves. On the other hand, the additives effective against oxidative refolding possessed a guanidium or ureido group. The former additives prevented hydrophobic interaction between the main chains of the unfolded polypeptide, while the latter additives increased the solubility of the aromatic and aliphatic side-chains. These data also support the fact that arginine (Arg) and Arg derivatives are versatile additives for both misfolding processes.

49 citations

Journal ArticleDOI
TL;DR: This paper shows amidated amino acids as new potent additives for controlling protein inactivation and aggregation and suggests the importance of amino and amide groups rather than the guanidium group as an aggregation suppressor.

47 citations

Journal ArticleDOI
TL;DR: In this article, a series of two-dimensional axisymmetric numerical computations are performed for methane-air flames over a sub-millimeter (constant inner diameter of 0.8mm) jet.

27 citations

Journal ArticleDOI
TL;DR: In this paper, a new concept based on the Damkohler number (Da) was proposed to describe the complete transition behavior found in a flame spread in a solid combustible tube.

18 citations


Cited by
More filters
Journal ArticleDOI
TL;DR: MORPHEUS is an initial protein crystallization screen with a unique organization which integrates components and ligands selected after analysing all crystal structure data deposited with the Protein Data Bank and local data gathered at the MRC Laboratory of Molecular Biology, Cambridge, England.
Abstract: A 96-condition initial screen for protein crystallization, called MORPHEUS, has been developed at the MRC Laboratory of Molecular Biology, Cambridge, England (MRC-LMB). The concept integrates several innovative approaches, such as chemically compatible mixes of potential ligands, new buffer systems and precipitant mixes that also act as cryoprotectants. Instead of gathering a set of crystallization conditions that have already been successful, a selection of molecules frequently observed in the Protein Data Bank (PDB) to co-crystallize with proteins has been made. These have been put together in mixes of similar chemical behaviour and structure, and combined with buffers and precipitant mixes that were also derived from PDB searches, to build the screen de novo. Observations made at the MRC-LMB and many practical aspects were also taken into account when formulating the screen. The resulting screen is easy to use, comprehensive yet small, and has already yielded a list of crystallization hits using both known and novel samples. As an indicator of success, the screen has now become one of the standard screens used routinely at the MRC-LMB when searching initial crystallization conditions for biological macromolecules.

240 citations

Journal ArticleDOI
20 Feb 2014
TL;DR: This review focuses on protein refolding techniques using chemical additives and laminar flow in microfluidic chips for the efficient recovery of active proteins from inclusion bodies.
Abstract: Biologically active proteins are useful for studying the biological functions of genes and for the development of therapeutic drugs and biomaterials in a biotechnology industry. Overexpression of recombinant proteins in bacteria, such as Escherichia coli, often results in the formation of inclusion bodies, which are protein aggregates with non-native conformations. As inclusion bodies contain relatively pure and intact proteins, protein refolding is an important process to obtain active recombinant proteins from inclusion bodies. However, conventional refolding methods, such as dialysis and dilution, are time consuming and, often, recovered yields of active proteins are low, and a trial-and-error process is required to achieve success. Recently, several approaches have been reported to refold these aggregated proteins into an active form. The strategies largely aim at reducing protein aggregation during the refolding procedure. This review focuses on protein refolding techniques using chemical additives and laminar flow in microfluidic chips for the efficient recovery of active proteins from inclusion bodies.

208 citations

Journal ArticleDOI
Yu Zhao1, Fuji Sakai1, Lu Su1, Yijiang Liu1, Kongchang Wei1, Guosong Chen1, Ming Jiang1 
TL;DR: This paper covers representative achievements in the fabrication of artificial building blocks for life, cell-inspired biomimetic materials, and macromolecular assemblies mimicking the functions of natural materials and their applications and demonstrates that MSA has played an important and irreplaceable role in the grand and long-standing research of biomimetics and bio-inspired materials.
Abstract: Macromolecular self-assembly (MSA) has been an active and fruitful research field since the 1980s, especially in this new century, which is promoted by the remarkable developments in controlled radical polymerization in polymer chemistry, etc. and driven by the demands in bio-related investigations and applications. In this review, we try to summarize the trends and recent progress in MSA in relation to biomimetic chemistry and bio-inspired materials. Our paper covers representative achievements in the fabrication of artificial building blocks for life, cell-inspired biomimetic materials, and macromolecular assemblies mimicking the functions of natural materials and their applications. It is true that the current status of the deliberately designed and obtained nano-objects based on MSA including a variety of micelles, multicompartment vesicles, and some hybrid and complex nano-objects is at their very first stage to mimic nature, but significant and encouraging progress has been made in achieving a certain similarity in morphologies or properties to that of natural ones. Such achievements also demonstrate that MSA has played an important and irreplaceable role in the grand and long-standing research of biomimetic and bio-inspired materials, the future success of which depends on mutual and persistent efforts in polymer science, material science, supramolecular chemistry, and biology.

205 citations

Journal ArticleDOI
TL;DR: The chemical effects of low-temperature atmospheric pressure plasma on protein in aqueous solution using lysozyme as a model showed decreased enzymatic activity and changed the secondary structure that results from the increased molecular weight of lyso enzyme with chemical modification.
Abstract: Plasma medicine is an attractive new research area, but fundamental information related to plasma modification of biomacromolecules in aqueous solution remains elusive. As described herein, we investigated the chemical effects of low-temperature atmospheric pressure plasma on protein in aqueous solution using lysozyme as a model. Plasma treatment decreased enzymatic activity and changed the secondary structure that results from the increased molecular weight of lysozyme with chemical modification. These effects arise neither from UV light nor from plasma heat, suggesting that the reactive species generated by the plasma affect lysozyme. The information presented in this paper represents a crucial first step for elucidating chemical reactions induced by plasma on proteins for biomedical applications.

155 citations

Book
01 Jan 2010
TL;DR: This poster presents a probabilistic procedure to characterize the polypeptide-by-polymethine ratio and its applications in medicine and on the basis of its properties as well as some experimental studies.
Abstract: Aggregation of therapeutic proteins , Aggregation of therapeutic proteins , کتابخانه مرکزی دانشگاه علوم پزشکی تهران

127 citations