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Marine Algal Secondary Metabolites Are a Potential Pharmaceutical Resource for Human Society Developments
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Somasundaram Ambiga, Raja Suja Pandian, Lazarus Vijune Lawrence, Arjun Pandian, Ramu Arun Kumar, Bakrudeen Ali Ahmed Abdul
Proteases enzymes, commonly known as biological catalysts, are responsible for a wide range of biochemical processes. They’ve been used in a variety of fields, especially therapeutics. The properties of molecules produced from the marine differ from those of their terrestrial counterparts. Marine microbes (epibionts and endosymbionts), which are abundant in unique environments, produce a plethora of medically and industrially essential molecules. These microbes secrete enzymes with specific characteristics like pH, metal, heat and cryo-tolerance and so on. Proteases are enzymes that break down lengthy chains of proteins into smaller fragments. Endopeptidases and exopeptidases are the two large families of proteases depending on their method of action. Exopeptidases degrade terminal amino acid positions attached to polypeptide chains, while endopeptidases catalyze the breakdown of peptide bonds in the middle portion of polypeptide chains. A further way of classifying proteases is by their optimum pH, which might be neutral, acidic, or alkaline. In terms of the active centers involved, enzymes can be classed as cysteine proteases, metalloproteases, serine proteases and aspartyl proteases.
Biodiscovery of Marine Microbial Enzymes in Indonesia
Published in Se-Kwon Kim, Marine Biochemistry, 2023
Ekowati Chasanah, Pujo Yuwono, Dewi Seswita Zilda, Siswa Setyahadi
Proteases are categorized as hydrolases, enzymes of class 3, subclass 3.4, peptide hydrolases or peptidase according to the Nomenclature Committee of the International Union of Biochemistry and Molecular Biology (Mamo & Assefa, 2018). They can be grouped as exopeptidases and endopeptidases; exopeptidase hydrolyzes the peptide bond proximal to the amino or carboxy terminal of the substrate, whereas endopeptidases cut the peptide bonds from the termini of the substrate. Based on the catalysis mechanism, that is, the hydrolysis of amide bonds in peptide substrates, proteases are classified as serine proteinases (EC 3.4.21), cysteine proteinases (EC 3.4.22), aspartyl proteinases (EC3.4.23), metalloproteinases (EC 3.4.24) and threonine peptidases (EC 3.4.25) (Kieliszek, Pobiega, Piwowarek, & Kot, 2021).
Proteinase Inhibitors: An Overview of their Structure and Possible Function in the Acute Phase
Published in Andrzej Mackiewicz, Irving Kushner, Heinz Baumann, Acute Phase Proteins, 2020
The chief characteristic of cystatins, as implied by their name, is the ability to inhibit cysteine proteinases. Cystatins do not inhibit proteinases with other catalytic mechanisms, and they are usually thought to be selective for cysteine proteinases of the papain superfamily, which include the lysosomal proteinases cathepsin B, H, and L, and the cytosolic calpains. Some evidence suggests that other types of cysteine proteinases, including clostripain and polioviral proteinases, may be inhibited, although the interactions have not been studied in detail. Members of this superfamily are unique among the inhibitors considered in this chapter, since some of the members of families 1 and 2 are able to inhibit the exopeptidase known as dipeptidyl peptidase I, an enzyme that sequentially removes dipeptides from the N terminus of proteins.
Subcutaneous catabolism of peptide therapeutics: bioanalytical approaches and ADME considerations
Published in Xenobiotica, 2022
Simone Esposito, Laura Orsatti, Vincenzo Pucci
The most relevant biotransformation occurring at the SC injection site is the cleavage of peptide bonds by means of proteases or peptidases, which generates smaller peptides or amino acids. This type of biotransformation is referred to as catabolism, in contrast to the term metabolism used for biotransformation mainly observed in small molecules. Proteolytic enzymes are broadly divided into two categories: exopeptidases, which catalyse the cleavage at the N-terminal or C-terminal removing a single amino acid, and endopeptidases, which cleave peptide bonds within the sequence (López-Otín and Bond 2008). Exopeptidases are intuitively divided into aminopeptidases and carboxypeptidases, while endopeptidases are traditionally classified on the basis of their catalytic site as cysteine peptidases (e.g. dipeptidyl peptidase IV), aspartic peptidases (e.g. pepsin), serine peptidases (e.g. cathepsin B), and metallopeptidases (e.g. matrix metalloprotease 2 and 9) (de Veer et al. 2014a).
Recent advances in proteolytic stability for peptide, protein, and antibody drug discovery
Published in Expert Opinion on Drug Discovery, 2021
Xianyin Lai, Jason Tang, Mohamed E.H. ElSayed
Three orthogonal approaches have been used to classify peptidases: the chemical mechanism of catalysis, the position of the reaction the peptidases catalyze, and the molecular structure and homology. Based on the chemical mechanism of catalysis, peptidases are classified as aspartic (A), cysteine (C), glutamic (G), metallo (M), asparagine (N), mixed (P), serine (S), threonine (T), or unknown (U) catalytic type [26,27]. Based on the position of the reactions that they catalyze, peptidases are grouped into exopeptidases that cleave a single amino acid, dipeptide, or dipeptide from the ends of a polypeptide sequence and endopeptidases that cleave peptide bonds between two amino acids within a polypeptide sequence. The exopeptidases are further divided into carboxypeptidases, aminopeptidases, dipeptidyl-peptidases, and tripeptidyl-peptidases. Based on the molecular structure and homology, peptidases under the nine chemical mechanisms mentioned above are further classified into clans that contain all peptidases from a single evolutionary origin. The clans are then further categorized into families that have a set of homologous proteolytic enzymes [28].
Bio-efficacy and physiological effects of Eucalyptus globulus and Allium sativum essential oils against Ephestia kuehniella Zeller (Lepidoptera: Pyralidae)
Published in Toxin Reviews, 2020
Morteza Shahriari, Arash Zibaee, Leila Shamakhi, Najmeh Sahebzadeh, Diana Naseri, Hassan Hoda
Activities of trypsin, chymotrypsin, and elastase proteases were assayed using specific substrates of Nabenzoyl-l-arginine-p-nitroanilide (BApNA, 1 mM), N-succinyl-alanine-alanine-proline-phenylalanine-p-nitroanilide (SAAPPpNA, 1 mM), and N-succinyl-alanine-alanine-alanine-p-nitroanilide (SAAApNA, 1 mM). The reaction mixture contained 30 µl of each substrate separately, 50 µl of universal buffer (20 mM, pH 8) and 15 µl of enzyme solution. The reaction mixture was incubated for 10 min at 30 °C. Then, absorbance was read at 405 nm (Oppert et al. 1997). Activities of exopeptidases were determined using Hippuryl-l-Phenilalanine and Hippuryl-l-Arginine for amino- and carboxypeptidase, respectively. Briefly, 30 μl of each substrate were separately added into 50 μl of universal buffer (20 mM, pH 8) and incubation was initiated by adding 15 μl of enzyme solution for 10 min at 30 °C. Then, absorbance was read at 340 nm (Oppert et al. 1997).