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Nanomaterials-Based Wearable Biosensors for Healthcare
Published in Sibel A. Ozkan, Bengi Uslu, Mustafa Kemal Sezgintürk, Biosensors, 2023
Jose Marrugo-Ramírez, L. Karadurmus, Miguel Angel Aroca, Emily P. Nguyen, Cecilia de Carvalho Castro e Silva, Giulio Rosati, Johann F. Osma, Sibel A. Ozkan, Arben Merkoçi
Cystic fibrosis (CF): CF is a life-limiting recessive genetic disease that affects the cells that produce mucus, sweat and digestive juices and causes serious damage to the lungs, digestive tract and other organs in the body. Early diagnosing of cystic fibrosis means that treatment can begin right away. Diagnosis is possible with some screening tests. A baby’s screening test checks for higher-than-normal levels of a chemical called immunoreactive trypsinogen (IRT), released by the pancreas, in a blood sample. However, IRT levels alone are not sufficient to confirm the diagnosis of cystic fibrosis and other tests may be required. In most cases, the diagnosis of CF is made because of the presence of one or more typical clinical features and then confirmed by demonstrating a high (>60 mmol/L) sweat chloride concentration (52–55).
Use of Enzymes in the Downstream Processing of Biopharmaceuticals
Published in Peter Grunwald, Pharmaceutical Biocatalysis, 2019
Another interesting example is found in the manufacturing of recombinant trypsin, an enzyme that is required as an ancillary material in the therapeutic recombinant insulin production mentioned above, as well as in biopharmaceutical manufacturing processes that use adherent cells (Section 2.3.1) (Muller et al., 2010; Merck Millipore, 2015). The enzyme is manufactured in the yeast Pichia pastoris as an inactive trypsinogen precursor, which is then converted into a mixture of α- and β-trypsin by a controlled auto-catalytic cleavage (Merck Millipore, 2015). In this process, small amounts of trypsin molecules (which may be added to accelerate the process) act as an activator of trypsinogen, releasing additional trypsin molecules that in turn act on more trypsinogen until substrate depletion. While the rate of trypsin production is very slow at first, it increases rapidly due to the auto-catalytic nature of the process (Vernon, 1913; Neurath and Dreyer, 1955; Muller et al., 2010).
Biodegradation Properties
Published in Chih-Chang Chu, J. Anthony von Fraunhofer, Howard P. Greisler, Wound Closure Biomaterials and Devices, 2018
These in vivo studies of the accelerated degradation of natural absorbable sutures, when exposed to alimentary tract fluids, are consistent with in vitro and in vivo studies. Jenkins and Hrdina observed that plain catgut sutures were digested in an average time of 11 h, and chromic catgut sutures in excess of 20 h, in HCl and pepsin solution.22 Okada also found that an accelerated loss of catgut suture mass and strength was found in a pH 1.6 aqueous solution (0.5% by weight NaCl) with a variety of concentrations of pepsin enzyme and the rate of weight loss depended on the concentration of pepsin.13 Mizuma et al. tested the loop-breaking strength of various sutures in saline, canine serum, bile, and activated and nonactivated pancreatic juice, and found that both plain and chromic catgut sutures disintegrated almost completely within 24 and 48 h, respectively, in enterokinase-activated pancreatic juice (i.e., trypsinogen was activated into trypsin).23 In an effort to explore the mechanism of degradation of the catgut sutures, the same authors used trypsin inhibitors, such as aprotinin and soybeans, to examine the rate of loss of loop strength of the sutures. It was found that these trypsin inhibitors did not protect the sutures from degradation.23 This suggests that trypsin may not be the major enzyme responsible for the degradation of catgut sutures.
Proteomic analysis of whole-body responses in medaka (Oryzias latipes) exposed to benzalkonium chloride
Published in Journal of Environmental Science and Health, Part A, 2020
Young Sang Kwon, Jae-Woong Jung, Yeong Jin Kim, Chang-Beom Park, Jong Cheol Shon, Jong-Hwan Kim, June-Woo Park, Sang Gon Kim, Jong-Su Seo
Trypsinogen (spot 11), which is related to cellular proteolysis, was upregulated by BAC exposure in a concentration-dependent manner. Trypsinogen is an inactive form of trypsin, a member of the serine protease family, which is generally involved in both lysosomal proteolysis and proteases (dipeptidase and peptidase).[65] A number of trypsinogen genes are expressed in the liver, pancreas, and lungs, and play a role in apoptosis.[66–68] In previous proteomic studies, gonadal trypsinogen expression was upregulated by exposure to tetrabromodiphenyl ether (BDE-47) in marine medaka (Oryzias melastigma),[69] in the liver of sweetfish (Plecoglossus altivelis) exposed to cadmium,[70] and in whole-body extracts of marine medaka fish (Oryzias javanicus) exposed to 4-nonlyphenol.[71] These results indicated that BAC potentially affects the cellular proteolytic system in medaka, and potentially that trypsinogen protein is overexpressed to counteract the damage caused by BAC toxicity.
Analysis of hydrolytic differences of free and “polyacrylic acid (PAAc)-conjugated trypsin and chymotrypsin” by using fluorescence lifetime distributions
Published in Preparative Biochemistry & Biotechnology, 2020
Ümmügülsüm Polat, İbrahim Ethem Özyiğit, Emine Karakuş
Trypsin and chymotrypsin in the proteolytic enzyme group are synthesized as inactive zymogen enzymes (trypsinogen and chymotrypsinogen) to avert undesirable breaking down of cellular proteins, and to regulate when and where enzyme activity occurs. These inactive zymogens are released into the duodenum, which is the peristaltic movement of the small and large intestines before being thrown away. Moreover, zymogens enter the bloodstream, where they can be found in serum prior to excretion in urine. Zymogens are turned into an active enzyme by proteolysis to split off a pro-peptide, either in a subcellular division or in an extracellular division where they are required for digestion. Although trypsin and chymotrypsin are structurally very similar, they bind different substrates. While trypsin has an effect on lysine and arginine residues, chymotrypsin acts on large hydrophobic residues such as tryptophan, tyrosine, and phenylalanine.[4]
Development of clone with novel TrpE fusion tag in E. coli for overexpression of trypsin in a bench-scale bioreactor
Published in Preparative Biochemistry & Biotechnology, 2021
Santhosh Nagaraj Nanjundaiah, Jayasri MA, Sunilkumar Sukumaran, Ganesh Sambasivam
Trypsin (EC 3.4.21.4) is a highly valuable serine protease of molecular weight 23.3 kDa, which targets basic amino acids such as lysine and arginine at the C-terminus. The zymogen form of the enzyme called trypsinogen gets converted to trypsin by the addition of either trypsin or enterokinase. Trypsin plays a major role in metabolism, digestion and coagulation in mammals.[1] Besides, the enzyme is useful in leather bating, food processing, pharmaceuticals and clinical diagnosis.[2] The application of trypsin in cell culture mainly lies in the removal of adherent cells from the culture surface and in the resuspension of cells.[3] The optimal pH for trypsin activity is 7–9, hence the formulation buffer should be of acidic pH to prevent self-activation.[4] To date, trypsin used in the laboratory as well as on the commercial scale is obtained from bovine and swine pancreas. Nonetheless, if extracted from these sources, the risk of microbial load being carried over even after the purification step is high.[5] The use of recombinant enzymes can help to overcome this complication. The bovine trypsin gene has been widely expressed in both prokaryotes and eukaryotes. Even though proteins are expressed without any fusion tag, the use of such tags are desirable as the enzymes are highly prone to degradation even when expressed in prokaryotic hosts. Fusion tags increase enzyme stability. However, the size of the tag is an important factor as it determines the final yield. The tag-protein ratio when using glutathione S transferase, maltose binding protein and thioredoxin fusion tag with trypsin is about 1:1–1:3. Although the expression levels are high, the total product percentage is only around 33–50% of the inclusion bodies produced. Besides, some amount of the protein is present in the soluble fraction, resulting in the reduction of yield after the purification and refolding steps. In order to convert the soluble fraction of protein into insoluble fraction, the use of an insoluble fusion partner with a hydrophobic core is desirable. In this context, the use of fusion tags that are less than 2 kDa in size and a ratio of up to 1:8–1:10 (tag: protein) might reduce the cost of production by increasing the protein yield. This approach could result in 80–90% of the protein being pushed into the inclusion bodies fraction.