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Biocatalyzed Synthesis of Antidiabetic Drugs
Published in Peter Grunwald, Pharmaceutical Biocatalysis, 2019
On the other hand, (4R)-hydroxyproline (Hyp) is a non-proteinogenic amino acid present in collagen, and whose abundance among the residues in animal proteins is very high, around 4%, a value calculated from the abundance of collagen among animal proteins (1/3) and that of Hyp within collagen (∼38% × 1/3). There are different biocatalyzed methodologies for the synthesis of Hyp; the most obvious one requires the employ of prolyl 4-hydroxylase (P4H, E.C. 1.14.11.2, also named procollagen-proline 4-dioxygenase), an 2-oxoacid dioxygenase requiring 2-oxoglutaric acid and molecular oxygen as cosubstrates (Gorres and Raines, 2010), as depicted in Fig. 11.30. Nevertheless, although there are many references for this procedure at lab scale (Hara et al., 2014; Yi et al., 2014; Chen et al., 2015; Pozzolini et al., 2015), its technical application is limited, because these 2-oxoacid dioxygenases are usually difficult to process (Huttel, 2013; Wu et al., 2016). Synthesis of Hyp catalyzed by P4H.
Greener Synthesis of Potential Drugs
Published in Ahindra Nag, Greener Synthesis of Organic Compounds, Drugs and Natural Products, 2022
Renata Studzińska, Renata Kołodziejska, Daria Kupczyk
The non-proteinogenic amino acid, which is a key intermediate required for the synthesis of drugs (e.g. Saxagliptin – a dipeptidyl peptidase IV inhibitor under development for the treatment of type 2 diabetes mellitus), can also be obtained by reductive amination in water. 2-(3-hydroxy-1-adamantyl)-2-oxoethanoic acid was converted to (S)-3-hydroxyadamantylglycine by reductive amination using a phenylalanine dehydrogenase from Thermoactinomyces intermedius (expressed in a modified form in Pichia pastoris or E. coli) with 95–100% yield (Scheme 12.22). NAD (nicotinamide adenine dinucleotide) produced during the reaction was recycled to NADH using formate dehydrogenase [158].
An exploration on the toxicity mechanisms of phytotoxins and their potential utilities
Published in Critical Reviews in Environmental Science and Technology, 2022
Huiling Chen, Harpreet Singh, Neha Bhardwaj, Sanjeev K. Bhardwaj, Madhu Khatri, Ki-Hyun Kim, Wanxi Peng
The cyanogenic glycosides (CGs) are a large class of secondary natural plant poisons that are widely distributed in the plant kingdom. Glycosides can be hydrolyzed to form sugar and non-sugar compounds by the dehydration/condensation of hydroxyl groups from (i) the hemiacetals of sugar or its derivatives (such as glucuronic acid) and (ii) non-sugar substances via acetal bonds (glycoside bonds). They are also called glycosides of α-hydroxynitrile. The first-ever reported CG, amygdalin, was extracted from almonds (Zoellner & Giebelmann, 2007). These molecules occur in the Pteridophyta, Gymnospermatophyta, and Angiospermatophyta plant phyla and Rosaceae, Linaceae, and Myrtaceae families. The most common CGs are monoglycosides such as linamarin and dhurrin. Glycosides can be classified into many groups, such as glucosinolates, cyanoglycosides, phenols, aromatic alcohols, and hydroxyanthraquinone derivatives (e.g., anthracene, flavonoids, flavonoid glycosides, coumarins, cardiac glycosides, and saponins). The biogenetic precursor molecules for CGs are protein amino acids such as L-valine, L-isoleucine, L-leucine, L-phenylalanine, and L-tyrosine and one non-proteinogenic amino acid (e.g., cyclopentenyl-glycine) (Cressey & Reeve, 2019; Vetter, 2000).
Extraction of keratin from unhairing of bovine hide
Published in Chemical Engineering Communications, 2022
Franck da Rosa de Souza, Jaqueline Benvenuti, Michael Meyer, Hauke Wulf, Enno Klüver, Mariliz Gutterres
The hydrolysis of keratin from hair requires breaking of disulfide bonds of the cystine amino acid residues from the polypeptide chain, and various pathways can be used for this purpose. The most common route is the so-called sulfitolysis, in which reducing agents containing sulfur react with cystine to cleave the bonds (Korniłłowicz-Kowalska and Bohacz 2011). This is the same principle of hair-burning unhairing (Hashem et al. 2017) and the chemical processes of permanent hair waving, in which thioglycolic acid is commonly used (Ogawa et al. 2009). A keratin hydrolysate could also be prepared using alkaline solutions with sodium hydroxide (Costa et al. 2011), and oxidizing agents (Marmer and Dudley 2006). The proteins with distinct characteristics compared to the native protein were obtained by keratin extraction oxidative routes (de Guzman et al. 2011). To cleave the cystine disulfide bond in the alkaline medium, certain reactions lead to the formation of lanthionine. This non-proteinogenic amino acid makes the hair much more difficult to dissolve, once the disulfide bond of the cysteine is replaced by the thioether linkage (Thakur and Balaram 2009). The effect of formic acid vapor on chicken keratin was also studied and concluded that it is possible to solubilize the material leading to the breakage of cystine bonds (Barone and Schmidt 2006).
Kinetic modeling and statistical optimization of submerged production of anti-Parkinson’s prodrug L-DOPA by Pseudomonas fluorescens
Published in Preparative Biochemistry & Biotechnology, 2022
Ananya Naha, Santosh Kumar Jha, Hare Ram Singh, Muthu Kumar Sampath
L-DOPA or Levodopa (l-3,4-dihydroxyphenylalanine) is a non-proteinogenic amino acid.[1] It is a drug of choice for Parkinson’s disease (PD), which is characterized by decreased levels of dopamine in the brain. James Parkinson first identified Parkinson’s disease as “The Shaking Palsy” in 1817.[2] Parkinson’s disease is the second global threat after the Alzheimer’s disease throughout the world. The projected global prevalence of PD supposed to accelerate to 2.89 million cases worldwide by 2022.[3]