Fast and Selective Reaction of 2-Benzylacrylaldehyde with 1,2-Aminothiol for Stable N-Terminal Cysteine Modification and Peptide Cyclization

In an attempt to identify polysaccharide components in thin sections of D. maydis, procedures were employed such that a PAS localization could be carried out. Three different fixatives were evaluated ie. glutaraldehyde, formaldehyde and paraformaldehyde. These were used in conjunction with periodic acid (PA), thiosemicarbazide(TSC), and osmium tetroxide(Os) to localize polysaccharides in V. maydis using a pre-embedded reaction procedure. Polysaccharide localization is based on the oxidation of vic-glycol groups by PA, and the binding of TSC as a selective reaction center for the formation of osmium black. The reaction product is sufficiently electron opaque, insoluble in lipids, not altered when tissue is embedded, and has a fine amorphous character.

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Mechanistic Study on Facet-Dependent Deposition of Metal Nanoparticles on Decahedral-Shaped Anatase Titania Photocatalyst Particles

Catalysts ◽

10.3390/catal8110542 ◽

2018 ◽

Vol 8 (11) ◽

pp. 542 ◽

Cited By ~ 4

Author(s):

Kenta Kobayashi ◽

Mai Takashima ◽

Mai Takase ◽

Bunsho Ohtani

Keyword(s):

Mechanistic Study ◽

Phase Reaction ◽

Surface Charges ◽

Platinum Nanoparticle ◽

Nanoparticle Deposition ◽

Selective Reaction ◽

Anatase Titania ◽

Deposition Density ◽

Titania Photocatalyst ◽

Source Materials

Facet-selective gold or platinum-nanoparticle deposition on decahedral-shaped anatase titania particles (DAPs) exposing {001} and {101} facets via photodeposition (PD) from metal-complex sources was reexamined using DAPs prepared with gas-phase reaction of titanium (IV) chloride and oxygen by quantitatively evaluating the area deposition density on {001} and {101} and comparing with the results of deposition from colloidal metal particles in the dark (CDD) or under photoirradiation (CDL). The observed facet selectivity, more or less {101} preferable, depended mainly on pH of the reaction suspensions and was almost non-selective at low pH regardless of the deposition method, PD or CDL, and the metal-source materials. Based on the results, the present authors propose that facet selectivity is attributable to surface charges (zeta potential) depending on the kind of facets, {001} and {101}, and pH of the reaction mixture and that this concept can explain the observed facet selectivity and possibly the reported facet selectivity without taking into account facet-selective reaction of photoexcited electrons and positive holes on {101} and {001} facets, respectively.

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PenA, a penicillin-binding protein-type thioesterase specialized for small peptide cyclization

Journal of Industrial Microbiology & Biotechnology ◽

10.1093/jimb/kuab023 ◽

2021 ◽

Author(s):

Kenichi Matsuda ◽

Kei Fujita ◽

Toshiyuki Wakimoto

Keyword(s):

Enzymatic Activity ◽

Computational Model ◽

Binding Protein ◽

Penicillin Binding Protein ◽

Small Peptide ◽

Peptide Cyclization ◽

Chain Lengths ◽

Non Ribosomal Peptides

Abstract Penicillin binding protein-type thioesterases (PBP-type TEs) are a recently identified group of peptide cyclases that catalyze head-to-tail macrolactamization of non-ribosomal peptides. PenA, a new member of this group, is involved in the biosyntheses of cyclic pentapeptides. In this study, we demonstrated the enzymatic activity of PenA in vitro, and analyzed its substrate scope with a series of synthetic substrates. A comparison of the reaction profiles between PenA and SurE, a representative PBP-type TE, showed that PenA is more specialized for small peptide cyclization. A computational model provided a possible structural rationale for the altered specificity for substrate chain lengths.

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Effect of cysteine modification on dihydrofolate reductase from a methotrexate-resistant strain of Escherichia coli B. Identification of modified residues.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(17)39930-1 ◽

1977 ◽

Vol 252 (19) ◽

pp. 6871-6877 ◽

Cited By ~ 4

Author(s):

M N Williams ◽

C D Bennett

Keyword(s):

Escherichia Coli ◽

Dihydrofolate Reductase ◽

Resistant Strain ◽

Cysteine Modification ◽

Escherichia Coli B

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Two-Dimensional Lateral Heterostructures Made by Selective Reaction on a Patterned Monolayer MoS2 Matrix

ACS Applied Materials & Interfaces ◽

10.1021/acsami.1c00725 ◽

2021 ◽

Author(s):

Xuewen Wang ◽

Bolun Wang ◽

Yonghuang Wu ◽

Enze Wang ◽

Hao Luo ◽

...

Keyword(s):

Two Dimensional ◽

Monolayer Mos2 ◽

Selective Reaction

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Selective Reaction of Aldehydes with Bicyclic Titanacyclopentadienes or Titanacyclopentenes Preparedin Situfrom 1,6- or 1,7-Diynes or Enynes and(η2-Propene)Ti(O-i-Pr)2

The Journal of Organic Chemistry ◽

10.1021/jo961340z ◽

1996 ◽

Vol 61 (20) ◽

pp. 6756-6757 ◽

Cited By ~ 33

Author(s):

Hirokazu Urabe ◽

Fumie Sato

Keyword(s):

Selective Reaction

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Development of a solid-phase extraction – spectrofluorimetric method for trace glutathione determination

Canadian Journal of Chemistry ◽

10.1139/v11-006 ◽

2011 ◽

Vol 89 (4) ◽

pp. 517-523 ◽

Cited By ~ 2

Author(s):

Ke-Jing Huang ◽

Cong-Hui Han ◽

Ying-Ying Wu ◽

Chao-Qun Han ◽

De-Jun Niu ◽

...

Keyword(s):

Solid Phase Extraction ◽

Limit Of Detection ◽

Solid Phase ◽

Signal To Noise Ratio ◽

Calibration Graph ◽

Extraction Column ◽

Phase Extraction ◽

Selective Reaction ◽

Spectrofluorimetric Method ◽

Relative Standard

A simple and efficient solid-phase extraction – spectrofluorimetric method has been developed to determine glutathione (GSH). Fluorescent probe N-(4,4-difluoro-5,7-dimethyl-4-bora-3a,4a-diaza-s-indacene-3-yl)methyl)iodoacetamide (BODIPY Fl-C1-IA) was used as the derivatization reagent. The procedure was based on a BODIPY Fl-C1-IA selective reaction with GSH to form the highly fluorescent product BODIPY Fl-C1-IA–GSH, using a solid-phase extraction column and spectrofluorimetric determination. The variables affecting analytical performance were studied and optimized. The calibration graph using the preconcentration system for GSH was linear over the range of 1–200 nmol/L with a limit of detection of 0.05 nmol/L (signal-to-noise ratio = 3). The relative standard deviation for six replicate determinations of GSH at the 100 nmol/L concentration level was 3.9%. The method was applied to water samples and average recoveries between 87.5% and 111.5% were obtained for spiked samples.

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