scholarly journals Synthesis ofβ-Amino Acids Using a Modified Hydantoinase Process as Enzymatic Reaction Cascade

2014 ◽  
Vol 86 (9) ◽  
pp. 1423-1423
Author(s):  
C. Slomka ◽  
U. Engel ◽  
C. Syldatk ◽  
J. Rudat
Marine Drugs ◽  
2019 ◽  
Vol 17 (12) ◽  
pp. 696
Author(s):  
Danqiong Huang ◽  
Wenfu Liu ◽  
Anguo Li ◽  
Chaogang Wang ◽  
Zhangli Hu

Haematococcus pluvialis is widely distributed in the world and well known as the richest natural source of astaxanthin that is a strong antioxidant with excellent commercial value. The pathway of astaxanthin biosynthesis in H. pluvialis has been documented as an enzymatic reaction. Several enzymes have been reported, but their isoforms or homologs have not been investigated genome-wide. To better understand the astaxanthin biosynthesis pathway in H. pluvialis, eight candidates of the geranylgeranyl pyrophosphate synthase gene (HpGGPPS) predicted from Iso-seq data were isolated in this study. The length of coding region of these candidates varied from 960 bp to 1272 bp, composing of 7–9 exons. The putative amino acids of all candidates composed the signature domain of GGPPS gene. However, the motifs in the domain region are varied, indicating different bio-functions. Phylogenetic analysis revealed eight candidates can be clustered into three groups. Only two candidates in Group1 encode the synthase participating in the astaxanthin formation. The yield of astaxanthin from these two candidates, 7.1 mg/g (DW) and 6.5 mg/g (DW) respectively, is significant higher than that from CrtE (2.4 mg/g DW), a GGPPS gene from Pantoea ananatis. This study provides a potential productive pathway for astaxanthin synthesis.


Zygote ◽  
1999 ◽  
Vol 8 (S1) ◽  
pp. S61-S61 ◽  
Author(s):  
Kazu Haino-Fukushima ◽  
Xuxi Fan ◽  
Shouka Nakamura

The vitelline coat (VC) lysin of Tegula, a marine molluscan genus, is released from the acrosome of sperm during fertilisation and can lyse the VC of only the same species. The lytic action of this lysin against the VC is not an enzymatic reaction, but a stoichiometric and irreversible one (Haino-Fukushima, 1974).The VC of Tegula pfeifferi consists of glycoproteins containing sulphated polysaccharides, which account for roughly two-thirds of the entire weight of the VC. The presence of a large quantity of polysaccharides in the VC had prevented rapid progress in the analysis of its protein components. Last year, we succeeded in a complete solubilisation of the VC by boiling for a long time in 1% SDS solution, and determined the cDNA sequence coding for a mature 41 kDa glycoprotein, which appears to be the major component of the VC from the results of SDS-polyacrylamide gel electrophoresis (PAGE). The cDNA, referred to as vcp41, comprises 1072 base pairs and contains one open reading frame with a sequence for 319 amino acids containing 19 amino acids of a signal peptide. The deduced amino acid sequence has five N-glycosylation sites and ten cysteine residues. It seems that almost 7 kDa in this 41kDa glycoprotein is polysaccharide constituents (Fan & Haino-Fukushima, 1998).


2020 ◽  
Vol 5 (9) ◽  
pp. 1043-1048
Author(s):  
F. J. Amaku ◽  
I. E. Otuokere ◽  
K. K. Igwe ◽  
O. V. Ikpeazu

This computational study comprises of pharmacophore-base virtual screening of the ZINC database, molecular docking of predicted ligands (pharmacophore agent) against the target protein, SARS-CoV-2 (PDB ID: 5r7y) and the prediction of ADMET descriptors using Swiss ADME and PROTOX-II online web servers.  Meanwhile,  remdesivir, ZINC72392503, ZINC72809903, ZINC06560017, ZINC76101700, ZINC88423098 and ZINC91600695 had a docking scores of -2.0 Kcal/mol, -6.7 Kcal/mol, -6.4 Kcal/mol, -6.0 Kcal/mol, -6.0 Kcal/mol, -6.0 Kcal/mol and-6.0 Kcal/mol respectively.  Meanwhile, ZINC72392503 was selected as the lead molecule and was observed to interact with LUE 27, THR 25, CYS 145, THR 26, SER 46, GLY 143, ASN 142, HIS 163, HIS 41, MET 165, GLU 166, ARG 188, GLN 189, HIS 41, MET 49, SER 46 amino acids.  The ADME descriptor revealed that the lead molecule was soluble, druggable, void of drug-drug interaction that may inhibit essential enzymatic reaction and was noticed to fall into PROTOX-II toxicity class 3.  The lead molecule showed a good affinity for the target protein of SARS-CoV-2, hence, may have a physiological implication that can inhibit a protein responsible for the replication of SARS-CoV-2.


2020 ◽  
Author(s):  
Gabriel Piedrafita ◽  
Sreejith Varma ◽  
Cecilia Castro ◽  
Christoph Messner ◽  
Lukasz Szyrwiel ◽  
...  

AbstractHow metabolic pathways emerged in early evolution remains largely unknown. Recently discovered chemical networks driven by iron and sulfur resemble reaction sequences found within glycolysis, gluconeogenesis, the oxidative and reductive Krebs cycle, the Wood Ljungdahl as well as the S-adenosylmethionine pathways, components of the core cellular metabolic network. These findings suggest that the evolution of central metabolism was primed by environmental chemical reactions, implying that non-enzymatic reaction networks served as a “template” in the evolution of enzymatic activities. We speculated that the turning point for this transition would depend on the catalytic properties of the simplest structural components of proteins, single amino acids. Here, we systematically combine constituents of Fe(II)-driven non-enzymatic reactions resembling glycolysis and pentose phosphate pathway (PPP), with single proteinogenic amino acids. Multiple reaction rates are enhanced by amino acids. In particular, cysteine is able to replace (and/or complement) the metal ion Fe(II) in driving the non-enzymatic formation of the RNA-backbone metabolite ribose 5-phosphate from 6-phosphogluconate, a rate-limiting reaction of the oxidative PPP. In the presence of both Fe(II) and cysteine, a complex is formed, enabling the non-enzymatic reaction to proceed at a wide range of temperatures. At mundane temperatures, this ‘minimal enzyme-like complex’ achieves a much higher specificity in the formation of ribose 5-phosphate than the Fe(II)-driven reaction at high temperatures. Hence, simple amino acids can accelerate key steps within metal-promoted metabolism-like chemical networks. Our results imply a stepwise scenario, in which environmental chemical networks served as primers in the early evolution of the metabolic network structure.Significance StatementThe evolutionary roots of metabolic pathways are barely understood. Here we show results consistent with a stepwise scenario during the evolution of (enzymatic) metabolism, starting from non-enzymatic chemical networks. By systematic screening of metabolic-like reactivities in vitro, and using high-throughput analytical techniques, we identify an iron/cysteine complex to act as a ‘minimal enzymelike complex’, which consists of a metal ion, an amino acid, and a sugar phosphate ligand. Integrated in a metal-driven, non-enzymatic pentose phosphate pathway, it promotes the formation of the RNA-backbone precursor ribose 5-phosphate at ambient temperature.


2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
J. A. Callejo-López ◽  
M. Ramírez ◽  
J. Bolívar ◽  
D. Cantero

The development of microalgae uses requires further investigation in cell disruption alternatives to reduce the costs associated to this processing stage. This study aimed to evaluate the main variables affecting an extraction method to obtain protein and amino acids from microalgae. The method was based on a sequential alkaline-enzymatic process, with separate extractions and noncontrolled pH, and was applied to fresh biomass of a resistant species. The processed microalgae were composed of a consortium with Nannochloropsis sp. as predominant species. After the optimization of the pH of the alkaline reaction, the effect of the time of the alkaline reaction (30–120 min), the time (30–120 min) and temperature (40–60°C) of the enzymatic reaction, and the biomass concentration (50–150 mg·ml−1), on the extraction yields of protein and free amino nitrogen (FAN) and on the final concentration of protein in the extract, was studied using a response surface methodology. Even though all the variables and some interactions among them had a significant effect, the biomass concentration was the most important factor affecting the overall process. The results showed relevant information about the different options in order to maximize not only the response variables individually but also different combinations of them. Assays with optimized values reached maximum yields of 80.3% and 1.07% of protein (% of total protein) and FAN (% of total biomass), respectively, and a protein concentration in the extract of 15.2 mg·ml−1. The study provided the essential information of an alternative approach to obtain protein and amino acids from fresh biomass of resistant microalgae with a high yield, also opening perspectives for further research in particular aspects.


2018 ◽  
Vol 475 (16) ◽  
pp. 2577-2592 ◽  
Author(s):  
Markus Ralser

Until recently, prebiotic precursors to metabolic pathways were not known. In parallel, chemistry achieved the synthesis of amino acids and nucleotides only in reaction sequences that do not resemble metabolic pathways, and by using condition step changes, incompatible with enzyme evolution. As a consequence, it was frequently assumed that the topological organisation of the metabolic pathway has formed in a Darwinian process. The situation changed with the discovery of a non-enzymatic glycolysis and pentose phosphate pathway. The suite of metabolism-like reactions is promoted by a metal cation, (Fe(II)), abundant in Archean sediment, and requires no condition step changes. Knowledge about metabolism-like reaction topologies has accumulated since, and supports non-enzymatic origins of gluconeogenesis, the S-adenosylmethionine pathway, the Krebs cycle, as well as CO2 fixation. It now feels that it is only a question of time until essential parts of metabolism can be replicated non-enzymatically. Here, I review the ‘accidents’ that led to the discovery of the non-enzymatic glycolysis, and on the example of a chemical network based on hydrogen cyanide, I provide reasoning why metabolism-like non-enzymatic reaction topologies may have been missed for a long time. Finally, I discuss that, on the basis of non-enzymatic metabolism-like networks, one can elaborate stepwise scenarios for the origin of metabolic pathways, a situation that increasingly renders the origins of metabolism a tangible problem.


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