Novel Immobilized Biocatalysts Based on Cysteine Proteases Bound to 2-(4-Acetamido-2-sulfanilamide) Chitosan and Research on Their Structural Features

Abstract

Briefly, 2-(4-Acetamido-2-sulfanilamide) chitosan, which is a chitosan water-soluble derivative, with molecular weights of 200, 350, and 600 kDa, was successfully synthesized. The immobilization of ficin, papain, and bromelain was carried out by complexation with these polymers. The interaction mechanism of 2-(4-acetamido-2-sulfanilamide) chitosan with bromelain, ficin, and papain was studied using FTIR spectroscopy. It was found that the hydroxy, thionyl, and amino groups of 2-(4-acetamido-2-sulfanilamide) chitosan were involved in the complexation process. Molecular docking research showed that all amino acid residues of the active site of papain formed hydrogen bonds with the immobilization matrix, while only two catalytically valuable amino acid residues took part in the H-bond formation for bromelain and ficin. The spectral and in silico data were in good agreement with the catalytic activity evaluation data. Immobilized papain was more active compared to the other immobilized proteases. Moreover, the total and specific proteolytic activity of papain immobilized on the carrier with a molecular weight of 350 kDa were higher compared to the native one due to the hyperactivation. The optimal ratio of protein content (mg × g −1 of carrier), total activity (U × mL−1 of solution), and specific activity (U × mg−1 of protein) was determined for the enzymes immobilized on 2-(4-acetamido-2-sulfanilamide) chitosan with a molecular weight of 350 kDa.

Conjugates of Chitosan with β-Cyclodextrins as Promising Carriers for the Delivery of Levofloxacin: Spectral and Microbiological Studies

“…On the ATR-FTIR spectrum of the compound obtained in the first stage ( Figure 1 b), absorption peaks are observed at the following wavenumbers: 1450 cm −1 (vibrations of the aromatic ring), 1190 cm −1 (sulfoether group) and 1020 cm −1 (skeleton vibrations of pyranose cycles) [ 31 ]. This spectral pattern corresponds to the expected one [ 32 ].…”

Novel Biocatalysts Based on Bromelain Immobilized on Functionalized Chitosans and Research on Their Structural Features

“…Finally, we compare the activity recovery of immobilized bromelain obtained in this work with our previously published results ( Figure 6 ). Earlier, we studied bromelain immobilization on chitosan (Ch) [ 46 ], 2-(4-acetamido-2-sulfanilamide) chitosan (SACh) [ 41 ], and chitosan copolymer with poly- N -vinylimidazole (Ch-g-PVI) [ 63 ]. As can be seen, the best activity recovery is achieved for bromelain immobilized on HTCCh and SACh, while for other proposed matrices, its value is dramatically low.…”

“…The immobilization of bromelain on the synthesized chitosan derivatives was performed using the complexation approach developed previously [ 41 ]. Firstly, 20 mL of enzyme solution (2 mg·mL −1 in 0.05 M trisodium borate buffer with a pH of 9.0) was added to 1 g of chitosan derivative (ChMC, HTCCh, ChS, or ChA) and incubated for 2 h at 37 °C.…”

Complexation of Bromelain, Ficin, and Papain with the Graft Copolymer of Carboxymethyl Cellulose Sodium Salt and N-Vinylimidazole Enhances Enzyme Proteolytic Activity

“…Our previously studies show that natural polymers, such as chitosan [2,14] and its derivatives [21][22][23][24] or nanoparticles based on it [25,26] are promising carriers for cysteine protease immobilization. This process can lead to enhance of proteolytic activity and make it possible to use immobilized enzymes as antibacterial and antibiofilm agents as well as in wound healing [2,27].…”