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When the K + channel-like protein Kesv from Ectocarpus siliculosus virus 1 is heterologously expressed in mammalian cells, it is sorted to the mitochondria. This targeting can be redirected to the endoplasmic reticulum (ER) by altering the codon usage in distinct regions of the gene or by inserting a triplet of hydrophobic amino acids (AAs) into the protein's C-terminal transmembrane domain (ct-TMD). Systematic variations in the flavor of the inserted AAs and/or its codon usage show that a positive charge in the inserted AA triplet alone serves as strong signal for mitochondria sorting. In cases of neutral AA triplets, mitochondria sorting are favored by a combination of hydrophilic AAs and rarely used codons; sorting to the ER exhibits the inverse dependency. This propensity for ER sorting is particularly high when a common codon follows a rarer one in the AA triplet; mitochondria sorting in contrast is supported by codon uniformity. Since parameters like positive charge, hydrophobic AAs, and common codons are known to facilitate elongation of nascent proteins in the ribosome the data suggest a mechanism in which local changes in elongation velocity and co-translational folding in the ct-TMD influence intracellular protein sorting., (© 2023 The Authors. Traffic published by John Wiley & Sons Ltd.)

To elucidate the effects of extracellular polymeric substance (EPS) on the sludge dewaterability, this study comparatively investigated the changes in EPS composition and spatial distribution, together with the sludge dewaterability after lysozyme (LZM) conditioning. The protein concentration in the tightly bound EPS (TB-EPS) increased from 3.47 mg g -1 DS to 4.99 mg g -1 DS within the first 2 min, then gradually decreased, which could be described by a piecewise linear function. Unlike TB-EPS, the protein content variation trend in both soluble EPS (S-EPS) and loosely bound EPS (LB-EPS) followed the typical first-order kinetics. Additionally, the extended DLVO theory was employed in combination with viscoelastic acoustic response analysis to further explore the impact of EPS composition on water adhesion and microbial cell. After the extraction of S-EPS from the conditioned sludge, the adsorption free energy (ΔG adh ) of EPS ascended to -61.05 mJ m -2 , indicating the weakened microbial hydrophobicity. By contrast, the ΔG adh value declined after the subsequent extraction of LB-EPS and TB-EPS. Meanwhile, the adsorption potential energy between S-EPS and microbial cells showed an increasing trend, whereas the repulsion potential energy between TB-EPS and microbial cells fell to 1.40 × 10 4  kT, signifying a weakened adsorption capacity to water. Accordingly, the viscosity and shear modulus of each EPS layer were reduced after conditioning, which contributed to the transformation of bound water into free water. These changes reasonably explained the results that the water content in the dewatered sludge after conditioning was reduced to 58.54%, and the bound water content decreased by 15.06%., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Polysaccharides, such as pectin, starch, alginate, carrageenan, and xanthan gum, have been used as biopolymer materials to create coatings and edible films to reduce traditional plastic packages. Petrochemical polymers, extensively used for food packaging, are non-renewable and non-biodegradable and need landfills. Thus, there is a requirement to find alternative packaging materials that are easily degradable and renewable. Natural edible polymers are the materials made from natural edible constituents that can be consumed by animals or human beings with no health risk. Since they are directly consumed with food, nothing is left for disposal. Polysaccharides, Protein and Lipid-Based Natural edible polymers are used to make coatings and edible films surrounding the surface of the food. These natural edible polymers are generally categorized into polysaccharides, lipids and proteins. This review article summarizes the importance of various natural polymers used for making coatings and edible films., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

This work deals with assessing the efficient performance of sodium caseinate (SC) as protein-based drug delivery system of niacin (NA) than carboxymethyl cellulose (CMC). In this respect the hydrogels from complexation of chitosan with sodium caseinate (SC/Ch) or sodium carboxymethyl cellulose (CMC/Ch) were prepared. The Synthesized NA free and loaded hydrogels were characterized by many techniques for examining the interaction, morphology, swelling, encapsulation efficiency (EE) and loading (L) % of niacin, as well as cytotoxicity study. The finding data showed the promising behavior of SC/Ch hydrogel than CMC/Ch hydrogel, toward the amount of loaded NA (95.6%) and in vitro slow sustained release up to 24 h. Whereas, the entrapment efficiency of the CMC/Ch to nicotinic acid was reached 85.6%, and it possessed highly initial burst release followed by a slower release up to 24 h. At pH 7.4 (simulated intestinal fluid) both hydrogels provided higher level of releasing profile to NA than pH 2.1 (gastric fluid). The NA release from hydrogels followed Fickian and non-Fickian diffusion mechanism according to pH 7.4 and 2.1, respectively. It is interesting to note that, the data obtained are higher than those obtained from literature reported hydrogel, e.g., poly (2-hydroxyethyl methacrylate). Neutral red uptake and lactate dehydrogenase assays confirmed both hydrogels have good biocompatibility and could be used as nontoxic drug delivery system. So, we recommended SC/Ch hydrogel as an effective controlled niacin drug delivery system with reducing systemic side effects and improved intestinal targeting efficiency., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Nonspecific protein deposition on Lyocell fibers via a cationization step was explored by adsorption of two different N,N,N-trimethyl chitosan chlorides (TMCs). Both, the cationization and the subsequent protein deposition steps were performed and monitored in situ by evaluating the zeta potential using the streaming potential method. Both employed TMCs (degree of substitution with N + Me 3 Cl groups: 0.27 and 0.64) irreversibly adsorb on the fibers as proven by charge reversal (-12 to +7mV for both derivatives) after the final rinsing step. Onto these cationized fibers, BSA was deposited at different pH values (4, 5, and 7). Charge titrations revealed that close to the isoelectric point of BSA (4.7), BSA deposition was particularly favored, while at lower pH values (pH 4), hardly any adsorption took place due to electrostatic repulsion of the cationic fibers and the positively charged BSA. This work sets the foundation for further investigations to use zeta potential measurements for protein adsorption studies on fibrous materials., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

We present an efficient approach to develop cellulose nanocrystal (CNC) hybrids with magnetically responsive Fe 3 O 4 nanoparticles that were synthesized using the (Fe 3+ /Fe 2+ ) coprecipitation. After 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-catalyzed oxidation of CNC, carbodiimide (EDC/NHS) was used for coupling amine-containing iron oxide nanoparticles that were achieved by dopamine ligand exchange (NH 2 -Fe 3 O 4 NPs). The as-prepared hybrids (Fe 3 O 4 @CNC) were further complexed with Cu(II) ions to produce specific protein binding sites. The performance of magnetically responsive Cu-Fe 3 O 4 @CNC hybrids was assessed by selectively separating lysozyme from aqueous media. The hybrid system displayed a remarkable binding capacity with lysozyme of 860.6 ± 14.6 mg/g while near full protein recovery (∼98%) was achieved by simple elution. Moreover, the regeneration of Fe 3 O 4 @CNC hybrids and efficient reutilization for protein separation was demonstrated. Finally, lysozyme separation from matrices containing egg white was achieved, thus revealing the specificity and potential of the presented method.

Cellulose accessibilities of a set of hornified lignocellulosic substrates derived by drying the never dried pretreated sample and a set of differently pretreated lodgepople pine substrates, were evaluated using solute exclusion and protein adsorption methods. Direct measurements of cellulase adsorption onto cellulose surface of the set of pretreated substrates were also carried out using an in situ UV-Vis spectrophotometric technique. The cellulose accessibilities measured by the solute exclusion and a cellulose-binding module (CBM)-containing green fluorescent protein (TGC) adsorption methods correlate well for both sets of samples. The substrate enzymatic digestibilities (SEDs) of the hornified substrates are proportional to the measured cellulose accessibilities. Approximately over 90% of the SED was contributed by the accessible pore surfaces of the hornified substrates, suggesting that the substrate external surface plays a minor role contributing to cellulose accessibility and SED. The cellulose accessibilities of the pretreated substrates correlated well with the amounts of cellulase adsorbed. The SEDs of these substrates directly correlated with the amounts of adsorbed cellulase., (Copyright © 2011 Wiley Periodicals, Inc.)