14379-64-7Relevant articles and documents
Remarkable Salt Effects in the Highly Enhanced Enantioselective Hydrolysis of Amino Acid Esters with the Active Tripeptide in the Vesicular System
Goto, Koichi,Imamura, Chikara,Yamamoto, Shinichi,Matsumoto, Yoko,Ueoka, Ryuichi
, p. 2081 - 2084 (1994)
The remarkably high enantioselectivity (kLa,obsd/kDa,obsd = 67) was attained along with the large rate-enhancement of the L-form substrate for the hydrolytic cleavage of N-dodecanoyl-D(L)-Phe-PNP by controlling the ionic strength ( = 0.03 M, 1 M = 1 mol dm-3) in the vesicular system.
Steric-control for the enantioselective hydrolysis of amino acid esters with membrane-bound enzyme models
Tanoue, Osamu,Baba, Manabu,Tokunaga, Yusuke,Goto, Koichi,Matsumoto, Yoko,Ueoka, Ryuichi
, p. 2129 - 2132 (1999)
The apparently complete stereoselectivity (K(L)(a,obsd)/k(D)(a,obsd)=(∞) for the hydrolysis of enantiomeric substrate (p-nitrophenyl n-dodecanoyl-D(L)-phenyalaninate; C(t2)-D(L)-Phe-PNP) catalyzed by active tripeptide (N-(benzyloxycarbonyl)-L-phenylalanyl-L- histidyl-L-leucine; Z-PheHisLeu) was attained by regulating the composition of coaggregates, ionic strength, and temperature, in coaggregate systems composed of vesicular and micellar surfactants. This can be related to the optimization of conformation in the Z-PheHisLeu catalyst to react with amino acid esters by changing of physical properties of coaggregates.
In search of bioinspired hydrogels from amphiphilic peptides: A template for nanoparticle stabilization for the sustained release of anticancer drugs
Mehra, Radha Rani,Tiwari, Priyanka,Basu, Anindya,Duttkonar, Anita
, p. 11666 - 11678 (2019/07/31)
The development of potent stimuli-responsive hydrogels has rapidly expanded in the last decades due to their diversified applications in the field of biomedicines. In accordance with this drift, herein, we aimed at modulating a series of amphiphilic peptide analogues with the general formula Me-(CH2)14-CO-NH-CH(X)-COOH, where X = CH2Ph in hydrogelators I (l-Phe) and II (d-Phe) and X = CH2Ph(OH) in hydrogelator III (l-Tyr), which displayed an excellent propensity to immobilize water at room temperature with a minimum gelation concentration of 0.04%/0.05%/0.02% w/v for hydrogelators I-III, respectively, regardless of their configuration at the C-terminal centre. To validate this threshold concentration difference, we performed computational analysis that demonstrated the ability of the side-chains of hydrogelators I and III to remain highly planar with the methylene units of the amphiphile and aromatic rings, promoting favourable correspondence through van der Waals forces and pi-pi stacking. Consequently hydrogelators I and III self-assembled in an ordered organisation superior to hydrogelator II. Furthermore, the spectroscopic and microscopic experiments revealed that the hydrogelators manifested a β-sheet conformation and nanofibrous morphology at the supramolecular level. As observed visually and additionally confirmed by differential scanning calorimetry (DSC) and rheological measurements, the hydrogels exhibited thermo-reversibility, injectability and high mechanical strength. Importantly, these biomaterials were also found to be resistant towards proteolytic degradation and non-cytotoxic in the cell line HEK 293 using a dose-dependant cell viability assay. To date, the development of a structured approach for the release of drugs in a predictable manner from an optimised formulation, using peptide-based hydrogel nanoparticles as a delivery system remains in its infancy. Hence, we developed hydrogel nanoparticles (HNPs) with our fabricated amphiphilic peptides that exploited the weak noncovalent interactions for their fabrication, unlike other cross-linked polymers that require strong covalent or ionic bonds for their formation. Interestingly, the as-synthesized nanoparticles showed an unprecedented ability to release the anticancer drugs 5-fluoro uracil/doxorubicin at physiological conditions depending on the physico-chemical parameters of the drugs. We believe that the reported injectable, biocompatible, amphiphilic peptide-based hydrogels hold future promise as a potential tool to transport drugs to a targeted site at a greater concentration, thus relieving the patient from surgical injury and simultaneously aiding in a faster recovery.
COMPOSITIONS IN THE FORM OF AN INJECTABLE AQUEOUS SOLUTION COMPRISING AMYLIN, AN AMYLIN RECEPTOR AGONIST OR AN AMYLIN ANALOG, AND A CO-POLYAMINO ACID
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Paragraph 0543-0546; 0623-0626, (2018/07/31)
An injectable aqueous solution, of which the pH is from 6.0 to 8.0, comprising at least: a) amylin, an amylin receptor agonist or an amylin analog; b) a co-polyamino acid bearing carboxylate charges and hydrophobic radicals Hy, said co-polyamino acid consisting of glutamic or aspartic units and said hydrophobic radicals Hy having the following formula I: [in-line-formulae]?GpR?r?GpA?a?GpC)p ??I[/in-line-formulae] wherein the composition does not comprise a basal insulin of which the isoelectric point pI is from 5.8 to 8.5. It also relates to a composition wherein it moreover comprises a prandial insulin.
