02542nas a2200241   4500008004100000022001400041245008900055210006900144260000900213300001600222490000800238520175100246100002501997700001502022700001702037700001702054700001902071700001902090700003202109700001802141700002002159856012102179       2023                        eng d  a0002-786300aCovalent organic framework cladding on peptide-amphiphile-based biomimetic catalysts0 aCovalent organic framework cladding on peptideamphiphilebased bi  cJUN   a12793-128010 v1453 a<p>
	Peptide-based biomimetic catalysts are promising materialsforefficient catalytic activity in various biochemical transformations.However, their lack of operational stability and fragile nature innon-aqueous media limit their practical applications. In this study,we have developed a cladding technique to stabilize biomimetic catalystswithin porous covalent organic framework (COF) scaffolds. This methodologyallows for the homogeneous distribution of peptide nanotubes insidethe COF (TpAzo and TpDPP) backbone, creating strong noncovalent interactionsthat prevent leaching. We synthesized two different peptide-amphiphiles,C10FFVK and C10FFVR, with lysine (K) and arginine(R) at the C-termini, respectively, which formed nanotubular morphologies.The C10FFVK peptide-amphiphile nanotubes exhibit enzyme-likebehavior and efficiently catalyze C-C bond cleavage in a buffermedium (pH 7.5). We produced nanotubular structures of TpAzo-C10FFVK and TpDPP-C10FFVK through COF claddingby using interfacial crystallization (IC). The peptide nanotubes encasedin the COF catalyze C-C bond cleavage in a buffer medium aswell as in different organic solvents (such as acetonitrile, acetone,and dichloromethane). The TpAzo-C10FFVK catalyst,being heterogeneous, is easily recoverable, enabling the reactionto be performed for multiple cycles. Additionally, the synthesis ofTpAzo-C10FFVK thin films facilitates catalysis inflow. As control, we synthesized another peptide-amphiphile, C10FFVR, which also forms tubular assemblies. By depositingTpAzo COF crystallites on C10FFVR nanotubes through IC,we produced TpAzo-C10FFVR nanotubular structuresthat expectedly did not show catalysis, suggesting the critical roleof the lysines in the TpAzo-C10FFVK.</p>
1 aMahato, Ashok, Kumar1 aPal, Sumit1 aDey, Kaushik1 aReja, Antara1 aPaul, Satyadip1 aShelke, Ankita1 aAjithkumar, Thalasseril, G.1 aDas, Dibyendu1 aBanerjee, Rahul  uhttps://library.ncl.res.in/content/covalent-organic-framework-cladding-peptide-amphiphile-based-biomimetic-catalysts02081nas a2200205   4500008004100000245009500041210006900136260000800205300000900213490000700222520140100229100001701630700001601647700002001663700001501683700001801698700001901716700001801735856012201753       2024                        eng d00aFeedback driven autonomous cycles of assembly and disassembly from minimal building blocks0 aFeedback driven autonomous cycles of assembly and disassembly fr  cNOV  a99800 v153 a<p>
	The construction of complex systems by simple chemicals that can display emergent network dynamics might contribute to our understanding of complex behavior from simple organic reactions. Here we design single amino acid/dipeptide-based systems that exhibit multiple periodic changes of (dis)assembly under non-equilibrium conditions in closed system, importantly in the absence of evolved biocatalysts. The two-component based building block exploits pH driven non-covalent assembly and time-delayed accelerated catalysis from self-assembled state to install orthogonal feedback loops with a single batch of reactants. Mathematical modelling of the reaction network establishes that the oscillations are transient for this network structure and helps to predict the relative contribution of the feedback loop to the ability of the system to exhibit such transient oscillation. Such autonomous systems with purely synthetic molecules are the starting point that can enable the design of active materials with emergent properties. The study of the network dynamics of complex systems formed by simple chemicals can contribute to our understanding of complex behavior from simple organic reactions. Here, built on the minimal building blocks, the authors describe a system with periodic (dis)assembly utilizing feedback loops controlled by time-delayed catalysis and pH-driven assembly.</p>
1 aReja, Antara1 aJha, Sangam1 aSreejan, Ashley1 aPal, Sumit1 aBal, Subhajit1 aGadgil, Chetan1 aDas, Dibyendu  uhttps://library.ncl.res.in/content/feedback-driven-autonomous-cycles-assembly-and-disassembly-minimal-building-blocks