27732-43-0Relevant academic research and scientific papers
Optogenetic Modulation of a Catalytic Biofilm for the Biotransformation of Indole into Tryptophan
Hu, Yidan,Liu, Xiaobo,Ren, Aloysius Teng Min,Gu, Ji-Dong,Cao, Bin
, p. 5142 - 5148 (2019)
In green chemical synthesis, biofilms as biocatalysts have shown great promise. Efficient biofilm-mediated biocatalysis requires the modulation of biofilm formation. Optogenetic tools are ideal to control biofilms because light is noninvasive, easily controllable, and cost-efficient. In this study, a gene circuit responsive to near-infrared (NIR) light was used to modulate the cellular level of bis-(3′-5′) cyclic dimeric guanosine monophosphate (c-di-GMP), a central regulator of the prokaryote biofilm lifestyle, which allowed the regulation of biofilm formation by using NIR light. The engineered biofilm was applied to catalyze the biotransformation of indole into tryptophan in submerged biofilm reactors and NIR-light-enhanced biofilm formation resulted in an approximately 30 % increase in tryptophan yield, which demonstrates the feasibility of the application of light to modulate the formation and performance of catalytic biofilms for chemical production. The c-di-GMP-targeted optogenetic approach to modulate catalytic biofilms showcases applications for biofilm-mediated biocatalysis.
Plants contain two distinct classes of functional tryptophan synthase beta proteins
Yin, Ruohe,Frey, Monika,Gierl, Alfons,Glawischnig, Erich
, p. 1667 - 1672 (2010)
Tryptophan synthase β-subunits (TSBs) catalyze the last step in tryptophan biosynthesis, i.e. The condensation of indole and serine yielding tryptophan. In microorganisms two subfamilies of TSBs (here designated as type 1 and type 2) are known, which are only distantly related. Surprisingly, in all genomes of multicellular plants analyzed genes encoding both types are present. While type 1 enzymes are well established as components of tryptophan synthase complexes, type 2 enzymes in plants have not yet been characterized. Tissue specific expression of the TSB genes from Arabidopsis thaliana was analyzed. While AtTSB1 is the predominantly expressed isoform in vegetative tissues, AtTSB1 and AtTSBtype2 reach similar transcript levels in seeds. AtTSBtype2 protein was expressed in Escherichia coli and purified. It converted indole and serine to tryptophan with a strikingly low Km-value for indole of ca. 74 nM. Attsbtype2 T-DNA insertion mutants showed no obvious deviation from the wild type phenotype, indicating that AtTSBtype2 function is not essential under standard growth conditions. As example for a monocot enzyme, maize TSB type 2 was analyzed and found to be transcribed in various tissues. ZmTSBtype2 was also catalytically active and here a Km-value for indole of ca. 7 μM was determined. These data indicate that TSB type 2 enzymes generally are functionally expressed in plants. Their potential biological role is discussed.
A tRNA-dependent two-enzyme pathway for the generation of singly and doubly methylated ditryptophan 2,5-diketopiperazines
Giessen, Tobias W.,Von Tesmar, Alexander M.,Marahiel, Mohamed A.
, p. 4274 - 4283 (2013)
A large number of bioactive natural products containing a 2,5-diketopiperazine (DKP) moiety have been isolated from various microbial sources. Especially tryptophan-containing cyclic dipeptides (CDPs) show great structural and functional diversity, while little is known about their biosynthetic pathways. Here, we describe the bioinformatic analysis of a cyclodipeptide synthase (CDPS)-containing gene cluster from Actinosynnema mirum spanning 2.9 kb that contains two putative DKP-modifying enzymes. We establish the biosynthetic pathway leading to two methylated ditryptophan CDPs through in vivo and in vitro analyses. Our studies identify the first CDPS (Amir-4627) that shows high substrate specificity synthesizing only one main product, cyclo(Trp-Trp) (cWW). It is the first member of the CDPS family that can form ditryptophan DKPs and the first prokaryotic CDPS whose main product constituents differ from the four amino acids (Phe, Leu, Tyr, and Met) usually found in CDPS-dependent CDPs. We show that after cWW formation a S-adenosyl-l-methionine- dependent N-methyltransferase (Amir-4628) conducts two successive methylations at the DKP-ring nitrogens and additionally show that it is able to methylate four other phenylalanine-containing CDPs. This makes Amir-4628 the first identified DKP-ring-modifying methyltransferase. The large number of known modifying enzymes of bacterial and fungal origin known to act upon Trp-containing DKPs makes the identification of a potent catalyst for cWW formation, encoded by a small gene, valuable for combinatorial in vivo as well as chemoenzymatic approaches, with the aim of generating derivatives of known CDP natural products or entirely new chemical entities with potentially improved or new biological activities.
Influence of the polarity of the medium on the catalysis of formation, rate of hydrolysis and stability of the Schiff bases formed by pyridoxal 5′-phosphate with L-tryptophan
Echevarria Gorostidi, Gerardo R.,Santos, Jose G.,Basagoitia, Andrea,Castillo, Marta,Garcia Blanco, Francisco
, p. 335 - 340 (2003)
The apparent rate constants of formation (k1) and hydrolysis (k2), and the equilibrium constant (KpH), of the Schiff bases formed by pyridoxal 5′-phosphate with L-tryptophan in water and different aqueous ethanol mixtures at a variable pH, 25 °C and an ionic strength of 0.1 M (1 M = 1 mol dm-3) were determined. The individual rate constants of formation and hydrolysis of the Schiff bases of the systems corresponding to the different chemical species present in the medium, as a function of its acidity, were also determined, as were the pK values for the Schiff bases. The influence of the solvent medium on the formation and hydrolysis rate constants of the Schiff bases is discussed.
Effects of polyhydroxy compounds on enzymatic synthesis of L-tryptophan catalyzed by tryptophan synthase
Xu, Lisheng,Wang, Zhiyuan,Liu, Junzhong,Mao, Pingting,Zhang, Hongjuan,Gao, Ji,Liu, Qian,Jiao, Qingcai
, p. 282 - 286 (2012)
The effects of polyethylene glycol (PEG) of different molecular (1000, 2000), glycerol, ethylene glycol on the catalytic activity of tryptophan synthase were studied. The results indicated that the addition of PEG 2000 increased the enzymatic activity of tryptophan synthase. The enzymatic activity of tryptophan synthase was enhanced 25.2% by 10 g L-1 PEG 2000. Reaction conditions were optimized by using 10 g L-1 PEG 2000 at pH 9 and 40 °C. L-Serine conversion rate reach 89.9% under the optimal conditions. The kinetic parameters indicated the specificity of TSase to substrate was improved. Graphical Abstract: The mechanism of reaction catalyzed by tryptophan synthase [Figure not available: see fulltext.]
Two-photon sensitive protecting groups operating via intramolecular electron transfer: Uncaging of GABA and tryptophan
Korzycka, Karolina A.,Bennett, Philip M.,Cueto-Diaz, Eduardo Jose,Wicks, Geoffrey,Drobizhev, Mikhail,Blanchard-Desce, Mireille,Rebane, Aleksander,Anderson, Harry L.
, p. 2419 - 2426 (2015)
Improved photo-labile protecting groups, with high sensitivity to two-photon excitation, are needed for the controlled release of drugs, as tools in neuroscience and physiology. Here we present a new modular approach to the design of caging groups based on photoinduced electron transfer from an electron-rich two-photon dye to an electron acceptor, followed by scission of an ester to release a carboxylic acid. Three different electron acceptors were tested: nitrobenzyl, phenacyl and pyridinium. The nitrobenzyl system was ineffective, giving only photochemical decomposition and no release of the carboxylic acid. The phenacyl system also performed poorly, liberating the carboxylic acid in 20% chemical yield and 0.2% photochemical yield. The pyridinium system was most successful, and was tested for the release of two carboxylic acids: γ-amino butyric acid (GABA) and tryptophan. The caged GABA undergoes photochemical cleavage with a chemical yield of >95% and a photochemical yield of 1%; it exhibits a two-photon absorption cross section of 1100 GM at 700 nm, corresponding to a two-photon uncaging cross section of 10 ± 3 GM. This journal is
Modular control ofl-tryptophan isotopic substitutionviaan efficient biosynthetic cascade
Buller, Andrew R.,Cavagnero, Silvia,McDonald, Allwin D.,Thompson, Clayton M.,Yang, Hanming
, p. 4189 - 4192 (2020)
Isotopologs are powerful tools for investigating biological systems. We report a biosynthetic-cascade synthesis of Trp isotopologs starting from indole, glycine, and formaldehyde using the enzymesl-threonine aldolase and an engineered β-subunit of tryptop
Enantioselective β-Replacement Reaction Mediated by an Artificial Enzyme Composed of a Hydrophobic Vitamin B6, Chiral Bilayer-forming Lipids, and Copper(II) Ions
Murakami, Yukito,Hisaeda, Yoshio,Miyajima, Tetsuya,Sakata, Hiroyuki,Kikuchi, Jun-ichi
, p. 645 - 648 (1993)
A hybrid bilayer membrane, composed of a synthetic lipid having an (S)-alanine residue, one having (S)-binaphthol and (S)-alanine moieties, a hydrophobic pyridoxal derivative, and copper(II) ions, exhibited a tryptophan synthase-like reactivity that affords tryptophan from serine and indole in an enantiomeric excess of the (S)-isomer.
Determination of the rates of formation and hydrolysis of the schiff bases formed by pyridoxal 5′-phosphate with L-tryptophan and its methyl and n-butyl esters
Echevarria Gorostidi, Gerardo R.,Santos, Jose G.,Basagoitia, Andrea,Garcia Blanco, Francisco
, p. 2471 - 2476 (2002)
The apparent rate constants of the formation (k1) and hydrolysis (k2) of the Schiff bases formed by pyridoxal 5′-phosphate with L-tryptophan and their methyl and n-butyl esters at a variable pH, 25 °C, and an ionic strength of 0.1 M were determined, along with the equilibrium constant (KpH). The individual rate constants of formation and hydrolysis of the Schiff bases of systems corresponding to different chemical species present in the medium as a function of its acidity were also determined, as were the pK values for the Schiff bases. The influence of the α-carboxyl group on the formation and hydrolysis constants of the Schiff bases, and also on their pK values, is demonstrated.
Recreating the natural evolutionary trend in key microdomains provides an effective strategy for engineering of a thermomicrobial N-demethylase
Gu, Zhenghua,Guo, Zitao,Shao, Jun,Shen, Chen,Shi, Yi,Tang, Mengwei,Xin, Yu,Zhang, Liang
, (2022/03/09)
N-demethylases have been reported to remove the methyl groups on primary or secondary amines, which could further affect the properties and functions of biomacromolecules or chemical compounds; however, the substrate scope and the robustness of N-demethylases have not been systematically investigated. Here we report the recreation of natural evolution in key microdomains of the Thermomicrobium roseum sarcosine oxidase (TrSOX), an N-demethylase with marked stability (melting temperature over 100 C) and enantioselectivity, for enhanced substrate scope and catalytic efficiency on -C-N-bonds. We obtained the structure of TrSOX by crystallization and X-ray diffraction (XRD) for the initial framework. The natural evolution in the nonconserved residues of key microdomains—including the catalytic loop, coenzyme pocket, substrate pocket, and entrance site—was then identified using ancestral sequence reconstruction (ASR), and the substitutions that accrued during natural evolution were recreated by site-directed mutagenesis. The single and double substitution variants catalyzed the N-demethylation of N-methyl-L-amino acids up to 1800- and 6000-fold faster than the wild type, respectively. Additionally, these single substitution variants catalyzed the terminal N-demethylation of non-amino-acid compounds and the oxidation of the main chain -C-N- bond to a -C=N- bond in the nitrogen-containing heterocycle. Notably, these variants retained the enantioselectivity and stability of the initial framework. We conclude that the variants of TrSOX are of great potential use in N-methyl enantiomer resolution, main-chain Schiff base synthesis, and alkaloid modification or degradation.
