Enzymatic synthesis and post-functionalization of two-dimensional crystalline cellulose oligomers with surface-reactive groups

2015 ◽  
Vol 51 (63) ◽  
pp. 12525-12528 ◽  
Author(s):  
Yusuke Yataka ◽  
Toshiki Sawada ◽  
Takeshi Serizawa

Two-dimensional crystalline cellulose oligomers with surface-reactive azide groups were synthesized by enzymatic reactions and covalently post-functionalized with alkyne-containing dye molecules through click reactions.

2014 ◽  
Vol 70 (a1) ◽  
pp. C1135-C1135
Author(s):  
Patrik Ahvenainen ◽  
Ritva Serimaa

Cellulose is the most abundant biopolymer on Earth and hence it has enormous potential as a source of renewable energy. The nanoscale properties of cellulose are also import for the wood and papermaking industries. The atomic level structure of naturally occurring cellulose Iβ allomorph is well known [1] and this atomistic model is employed in this study for the cellulose unit cell structure. The cellulose crystallinity cannot be measured directly with scattering methods, but the crystallinity of the sample can be estimated by fitting models of crystalline and amorphous contributions to the sample intensity profile. The crystallinity fitting can be enhanced by improving the cellulose fitting model or the amorphous model. We focus on the cellulose crystallite model. The nanoscale level organization of crystalline cellulose in different plant materials is less well established that the unit cell structure of cellulose Iβ. Information on the texture of the sample is obtained efficiently by measuring the sample with a two-dimensional detector. The two-dimensional diffraction pattern can be used to obtain a wealth of information in one measurement, including the crystallite size, crystallite orientation and the crystallinity of the sample. The small size of cellulose crystallites in the wood cell wall limits the information obtainable from the diffraction pattern as the diffraction peaks widen and overlap. The overlapping of certain diffraction peaks can be studied at least qualitatively by computing the diffraction patterns from crystallite models of varying dimensions. Different models for cellulose crystallite have been suggested in the literature, such as the 36 chain model [2]. We investigate how the crystallinity fitting is influenced by the selected cellulose crystallite model and evaluate the suitability of different models to experimental X-ray scattering data of plant material, wood and highly crystalline cellulose.


2020 ◽  
Vol 1 (2) ◽  
pp. 146-152 ◽  
Author(s):  
Satheeshkumar Elumalai ◽  
John R. Lombardi ◽  
Masahiro Yoshimura

The resonance Raman signal enhancement of crystal violet dyes onto the two-dimensional MXene–Ti3C2Tx film, so called MXenes-enhanced resonance Raman scattering (MERRS), is reported with a calculated enhancement factor of 3.42 × 109.


2015 ◽  
Vol 11 ◽  
pp. 335-347 ◽  
Author(s):  
Miriam Goll ◽  
Adrian Ruff ◽  
Erna Muks ◽  
Felix Goerigk ◽  
Beatrice Omiecienski ◽  
...  

The electrocopolymerization of 3,4-ethylenedioxythiophene (EDOT) with the branched thiophene building block 2,2′:3′,2″-terthiophene (3T) is presented as a versatile route to functional polymer films. Comparisons to blend systems of the respective homopolymers PEDOT and P3T by in situ spectroelectrochemistry and Raman spectroscopy prove the successful copolymer formation and the access to tailored redox properties and energy levels. The use of EDOT-N3 as co-monomer furthermore allows modifications of the films by polymer analogous reactions. Here, we exemplarily describe the post-functionalization with ionic moieties by 1,3-dipolar cycloaddition (“click”-chemistry) which allows to tune the surface polarity of the copolymer films from water contact angles of 140° down to 40°.


2007 ◽  
Vol 189 (6) ◽  
pp. 2300-2309 ◽  
Author(s):  
Jean-Charles Blouzard ◽  
Caroline Bourgeois ◽  
Pascale de Philip ◽  
Odile Valette ◽  
Anne Bélaïch ◽  
...  

ABSTRACT The enzyme diversity of the cellulolytic system produced by Clostridium cellulolyticum grown on crystalline cellulose as a sole carbon and energy source was explored by two-dimensional electrophoresis. The cellulolytic system of C. cellulolyticum is composed of at least 30 dockerin-containing proteins (designated cellulosomal proteins) and 30 noncellulosomal components. Most of the known cellulosomal proteins, including CipC, Cel48F, Cel8C, Cel9G, Cel9E, Man5K, Cel9M, and Cel5A, were identified by using two-dimensional Western blot analysis with specific antibodies, whereas Cel5N, Cel9J, and Cel44O were identified by using N-terminal sequencing. Unknown enzymes having carboxymethyl cellulase or xylanase activities were detected by zymogram analysis of two-dimensional gels. Some of these enzymes were identified by N-terminal sequencing as homologs of proteins listed in the NCBI database. Using Trap-Dock PCR and DNA walking, seven genes encoding new dockerin-containing proteins were cloned and sequenced. Some of these genes are clustered. Enzymes encoded by these genes belong to glycoside hydrolase families GH2, GH9, GH10, GH26, GH27, and GH59. Except for members of family GH9, which contains only cellulases, the new modular glycoside hydrolases discovered in this work could be involved in the degradation of different hemicellulosic substrates, such as xylan or galactomannan.


Molecules ◽  
2018 ◽  
Vol 23 (11) ◽  
pp. 2797 ◽  
Author(s):  
Ting-Ting Zhang ◽  
Ting Gong ◽  
Zong-Feng Hu ◽  
An-Di Gu ◽  
Jin-Ling Yang ◽  
...  

Glycosylation, which is catalyzed by UDP-glycosyltransferases (UGTs), is an important biological modification for the structural and functional diversity of ginsenosides. In this study, the promiscuous UGT109A1 from Bacillus subtilis was used to synthesize unnatural ginsenosides from natural ginsenosides. UGT109A1 was heterologously expressed in Escherichia coli and then purified by Ni-NTA affinity chromatography. Ginsenosides Re, Rf, Rh1, and R1 were selected as the substrates to produce the corresponding derivatives by the recombinant UGT109A1. The results showed that UGT109A1 could transfer a glucosyl moiety to C3-OH of ginsenosides Re and R1, and C3-OH and C12-OH of ginsenosides Rf and Rh1, respectively, to produce unnatural ginsenosides 3,20-di-O-β-d-glucopyranosyl-6-O-[α-l-rhamnopyrano-(1→2)-β-d-glucopyranosyl]-dammar-24-ene-3β,6α,12β,20S-tetraol (1), 3,20-di-O-β-d-glucopyranosyl-6-O-[β-d-xylopyranosyl-(1→2)-β-d-glucopyranosyl]-dammar-24-ene-3β,6α,12β,20S-tetraol (6), 3-O-β-d-glucopyranosyl-6-O-[β-d-glucopyranosyl-(1→2)-β-d-glucopyranosyl]-dammar-24-ene-3β,6α,12β,20S-tetraol (3), 3,12-di-O-β-d-glucopyranosyl-6-O-[β-d-glucopyranosyl-(1→2)-β-d-glucopyranosyl]-dammar-24-ene-3β,6α,12β,20S-tetraol (2), 3,6-di-O-β-d-glucopyranosyl-dammar-24-ene-3β,6α,12β,20S-tetraol (5), and 3,6,12-tri-O-β-d-glucopyranosyl-dammar-24-ene-3β,6α,12β,20S-tetraol (4). Among the above products, 1, 2, 3, and 6 are new compounds. The maximal activity of UGT109A1 was achieved at the temperature of 40 °C, in the pH range of 8.0–10.0. The activity of UGT109A1 was considerably enhanced by Mg2+, Mn2+, and Ca2+, but was obviously reduced by Cu2+, Co2+, and Zn2+. The study demonstrated that UGT109A1 was effective in producing a series of unnatural ginsenosides through enzymatic reactions, which could pave a way to generate promising leads for new drug discovery.


2007 ◽  
Vol 346 (1) ◽  
pp. 162-167 ◽  
Author(s):  
Noritaka Kato ◽  
Ichiro Hirosawa ◽  
Masugu Sato ◽  
Naoshi Ikeda ◽  
Ken-Ichi Iimura ◽  
...  

2016 ◽  
Vol 52 (88) ◽  
pp. 12984-12987 ◽  
Author(s):  
Hai-Long Liu ◽  
Yu-Jie Chang ◽  
Ting Fan ◽  
Zhi-Yuan Gu

Stable 2-D metal–organic framework nanosheets as a MALDI matrix for small molecule analysis and monitoring enzymatic reactions at high salt concentrations.


2000 ◽  
Vol 660 ◽  
Author(s):  
Noritaka Kato ◽  
Yasuaki Shin ◽  
Yoshiaki Uesu

ABSTRACTOn the subphase, which contains Cd2+ and Mg2+ ions, two-dimensional (2D) J-aggregate crystallites of merocyanine dye molecules exhibit a thermochromic transition. The J-aggregate absorption band of the low (LT) and high temperature (HT) phases are located at 620 and 595 nm, respectively. In order to clarify the in-plane structure of the 2D J-aggregate crystallites, grazing incident X-ray diffraction measurements were performed on the Langmuir-Blodgett multi-layers which consisted of the monolayers of LT and HT phases. It was revealed that the in-plane arrangement of the dye molecules is slightly different in the J-aggregate crystallites of LT and HT phases.


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