scholarly journals Purification, Characterization, and Application of a Novel Dye-Linked l-Proline Dehydrogenase from a Hyperthermophilic Archaeon, Thermococcus profundus

2001 ◽  
Vol 67 (4) ◽  
pp. 1470-1475 ◽  
Author(s):  
Haruhiko Sakuraba ◽  
Yoshinori Takamatsu ◽  
Takenori Satomura ◽  
Ryushi Kawakami ◽  
Toshihisa Ohshima

ABSTRACT The distribution of dye-linked l-amino acid dehydrogenases was investigated in several hyperthermophiles, and the activity of dye-linked l-proline dehydrogenase (dye-l-proDH, l-proline:acceptor oxidoreductase) was found in the crude extract of someThermococcales strains. The enzyme was purified to homogeneity from a hyperthermophilic archaeon, Thermococcus profundus DSM 9503, which exhibited the highest specific activity in the crude extract. The molecular mass of the enzyme was about 160 kDa, and the enzyme consisted of heterotetrameric subunits (α2 β2) with two different molecular masses of about 50 and 40 kDa. The N-terminal amino acid sequences of the α-subunit (50-kDa subunit) and the β-subunit (40-kDa subunit) were MRLTEHPILDFSERRGRKVTIHF and XRSEAKTVIIGGGIIGLSIAYNLAK, respectively. Dye-l-proDH was extraordinarily stable among the dye-linked dehydrogenases under various conditions: the enzyme retained its full activity upon incubation at 70°C for 10 min, and ca. 40% of the activity still remained after heating at 80°C for 120 min. The enzyme did not lose the activity upon incubation over a wide range of pHs from 4.0 to 10.0 at 50°C for 10 min. The enzyme exclusively catalyzed l-proline dehydrogenation using 2,6-dichloroindophenol (Cl2Ind) as an electron acceptor. The Michaelis constants for l-proline and Cl2Ind were determined to be 2.05 and 0.073 mM, respectively. The reaction product was identified as Δ1-pyrroline-5-carboxylate by thin-layer chromatography. The prosthetic group of the enzyme was identified as flavin adenine dinucleotide by high-pressure liquid chromatography. In addition, the simple and specific determination of l-proline at concentrations from 0.10 to 2.5 mM using the stable dye-l-proDH was achieved.

2020 ◽  
Vol 44 (3) ◽  
pp. 177-189
Author(s):  
Momir Dunjic ◽  
Stefano Turini ◽  
Dejan Krstic ◽  
Katarina Dunjic ◽  
Marija Dunjic ◽  
...  

Radiofrequency therapy is an unconventional method, already applied for some time, with numerous results in numerous clinical pictures. Our group has developed a software, later called SONGENPROT-SOLARIS, capable of directly converting nucleotide sequences (DNA and/or RNA) and amino acid sequences (polypeptides and proteins) into musical sequences, based on mathematic matrices, designed by the French physicist and musician Joel Sternheimer, which allows to associate a musical note with a nucleotide or an amino acid. Innovation in our software is that, in the algorithm that defines it, a variant is directly implemented that allows the reproduction of sounds, phase-shifted by 30 Hz, between one ear and another reproducing the phenomenon of Binaural Tones, capable of induce a specific brain activity and also the release of particles called solitons. Thanks to this software we have developed a technique called MMT (Molecular Music Therapy) and currently, we are in the phase of applying the technique on a cohort of 91 patients, with a high spectrum of clinical pictures, examining the same, using the technique Bi-Digital-ORing-Test (BDORT), before and after treatment with MMT. Aim of project is to stimulate the expression of a specific gene (the same genetic sequence that the patient listens to, translated into music), only through the use of sound sequences. We have concentrated our attention on three main molecules: Sirtuin-1, Telomers and TP-53. The results obtained with BDORT, after treatment with MMT, showed a significant increase in the values of the three molecules, on all the examined patients, demonstrating the operative efficacy of the technique and the its applicability to numerous diseases. In order to confirm the data obtained by BDORT, we propose, with the help of an accredited laboratory, to perform epigenetic tests on the three parameters listed above, paving the way to understanding how frequencies can influence gene expression.


2021 ◽  
Author(s):  
Amrutha Bindu ◽  
Lakshmi Devi

Abstract The focus of present study was to characterize antimicrobial peptide produced by probiotic cultures, Enterococcus durans DB-1aa (MCC4243), Lactobacillus plantarum Cu2-PM7 (MCC4246) and Lactobacillus fermentum Cu3-PM8 (MCC4233) against Staphylococus aureus and E. coli. The growth kinetic assay revealed 24 h of incubation to be optimum for bacteriocin production. The partially purified compound after ion-exchange chromatography was found to be thermoresistant and stable under wide range of pH. The compound was sensitive to proteinase-K, but resistant to trypsin, a-amylase and lipase. The apparent molecular weight of bacteriocin from MCC4243 and MCC4246 was found to be 3.5 KDa. Translated partial amino acid sequence of plnA gene in MCC4246 displayed 48 amino acid sequences showing 100% similarity with plantaricin A of Lactobacillus plantarum (WP_0036419). The sequence revealed 7 β sheets, 6 α sheets, 6 predicted coils and 9 predicted turns. The functions on cytoplasm show 10.82 isoelectric point and 48.6% hydrophobicity. The molecular approach of using Geneious Prime software and protein prediction data base for characterization of bacteriocin is novel and predicts “KSSAYSLQMGATAIKQVKKLFKKWGW” as peptide responsible for antimicrobial activity. The study provides information about broad spectrum bacteriocin in native probiotic culture and paves a way towards its application in functional foods as biopreservative agents.


2002 ◽  
Vol 184 (12) ◽  
pp. 3305-3312 ◽  
Author(s):  
Taku Amo ◽  
Haruyuki Atomi ◽  
Tadayuki Imanaka

ABSTRACT We had previously isolated a facultatively anaerobic hyperthermophilic archaeon, Pyrobaculum calidifontis strain VA1. Here, we found that strain VA1, when grown under aerobic conditions, harbors high catalase activity. The catalase was purified 91-fold from crude extracts and displayed a specific activity of 23,500 U/mg at 70°C. The enzyme exhibited a Km value of 170 mM toward H2O2 and a k cat value of 2.9 × 104 s−1·subunit−1 at 25°C. Gel filtration chromatography indicated that the enzyme was a homotetramer with a subunit molecular mass of 33,450 Da. The purified catalase did not display the Soret band, which is an absorption band particular to heme enzymes. In contrast to typical heme catalases, the catalase was not strongly inhibited by sodium azide. Furthermore, with plasma emission spectroscopy, we found that the catalase did not contain iron but instead contained manganese. Our biochemical results indicated that the purified catalase was not a heme catalase but a manganese (nonheme) catalase, the first example in archaea. Intracellular catalase activity decreased when cells were grown anaerobically, while under aerobic conditions, an increase in activity was observed with the removal of thiosulfate from the medium, or addition of manganese. Based on the N-terminal amino acid sequence of the purified protein, we cloned and sequenced the catalase gene (katPc ). The deduced amino acid sequence showed similarity with that of the manganese catalase from a thermophilic bacterium, Thermus sp. YS 8-13. Interestingly, in the complete archaeal genome sequences, no open reading frame has been assigned as a manganese catalase gene. Moreover, a homology search with the sequence of katPc revealed that no orthologue genes were present on the archaeal genomes, including those from the “aerobic” (hyper)thermophilic archaea Aeropyrum pernix, Sulfolobus solfataricus, and Sulfolobus tokodaii. Therefore, Kat Pc can be considered a rare example of a manganese catalase from archaea.


Author(s):  
Siyan Zhao ◽  
Chen Zhang ◽  
Matthew J. Rogers ◽  
Xuejie Zhao ◽  
Jianzhong He

As a group, Dehalococcoides dehalogenate a wide range of organohalide pollutants but the range of organohalide compounds that can be utilized for reductive dehalogenation differs among the Dehalococcoides strains. Dehalococcoides lineages cannot be reliably disambiguated in mixed communities using typical phylogenetic markers, which often confounds bioremediation efforts. Here, we describe a computational approach to identify Dehalococcoides genetic markers with improved discriminatory resolution. Screening core genes from the Dehalococcoides pangenome for degree of similarity and frequency of 100% identity found a candidate genetic marker encoding a bacterial neuraminidase repeat (BNR)-containing protein of unknown function. This gene exhibits the fewest completely identical amino acid sequences and among the lowest average amino acid sequence identity in the core pangenome. Primers targeting BNR could effectively discriminate between 40 available BNR sequences ( in silico ) and 10 different Dehalococcoides isolates ( in vitro ). Amplicon sequencing of BNR fragments generated from 22 subsurface soil samples revealed a total of 109 amplicon sequence variants, suggesting a high diversity of Dehalococcoides distributed in environment. Therefore, the BNR gene can serve as an alternative genetic marker to differentiate strains of Dehalococcoides in complicated microbial communities. Importance The challenge of discriminating between phylogenetically similar but functionally distinct bacterial lineages is particularly relevant to the development of technologies seeking to exploit the metabolic or physiological characteristics of specific members of bacterial genera. A computational approach was developed to expedite screening of potential genetic markers among phylogenetically affiliated bacteria. Using this approach, a gene encoding a bacterial neuraminidase repeat (BNR)-containing protein of unknown function was selected and evaluated as a genetic marker to differentiate strains of Dehalococcoides , an environmentally relevant genus of bacteria whose members can transform and detoxify a range of halogenated organic solvents and persistent organic pollutants, in complex microbial communities to demonstrate the validity of the approach. Moreover, many apparently phylogenetically distinct, currently uncharacterized Dehalococcoides were detected in environmental samples derived from contaminated sites.


Life ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 8 ◽  
Author(s):  
Michael S. Wang ◽  
Kenric J. Hoegler ◽  
Michael H. Hecht

Life as we know it would not exist without the ability of protein sequences to bind metal ions. Transition metals, in particular, play essential roles in a wide range of structural and catalytic functions. The ubiquitous occurrence of metalloproteins in all organisms leads one to ask whether metal binding is an evolved trait that occurred only rarely in ancestral sequences, or alternatively, whether it is an innate property of amino acid sequences, occurring frequently in unevolved sequence space. To address this question, we studied 52 proteins from a combinatorial library of novel sequences designed to fold into 4-helix bundles. Although these sequences were neither designed nor evolved to bind metals, the majority of them have innate tendencies to bind the transition metals copper, cobalt, and zinc with high nanomolar to low-micromolar affinity.


2001 ◽  
Vol 183 (15) ◽  
pp. 4468-4476 ◽  
Author(s):  
Franz Kaufmann ◽  
Derek R. Lovley

ABSTRACT NADPH is an intermediate in the oxidation of organic compounds coupled to Fe(III) reduction in Geobacter species, but Fe(III) reduction with NADPH as the electron donor has not been studied in these organisms. Crude extracts of Geobacter sulfurreducens catalyzed the NADPH-dependent reduction of Fe(III)-nitrilotriacetic acid (NTA). The responsible enzyme, which was recovered in the soluble protein fraction, was purified to apparent homogeneity in a four-step procedure. Its specific activity for Fe(III) reduction was 65 μmol · min−1 · mg−1. The soluble Fe(III) reductase was specific for NADPH and did not utilize NADH as an electron donor. Although the enzyme reduced several forms of Fe(III), Fe(III)-NTA was the preferred electron acceptor. The protein possessed methyl viologen:NADP+ oxidoreductase activity and catalyzed the reduction of NADP+ with reduced methyl viologen as electron donor at a rate of 385 U/mg. The enzyme consisted of two subunits with molecular masses of 87 and 78 kDa and had a native molecular mass of 320 kDa, as determined by gel filtration. The purified enzyme contained 28.9 mol of Fe, 17.4 mol of acid-labile sulfur, and 0.7 mol of flavin adenine dinucleotide per mol of protein. The genes encoding the two subunits were identified in the complete sequence of the G. sulfurreducens genome from the N-terminal amino acid sequences derived from the subunits of the purified protein. The sequences of the two subunits had about 30% amino acid identity to the respective subunits of the formate dehydrogenase from Moorella thermoacetica, but the soluble Fe(III) reductase did not possess formate dehydrogenase activity. This soluble Fe(III) reductase differs significantly from previously characterized dissimilatory and assimilatory Fe(III) reductases in its molecular composition and cofactor content.


1989 ◽  
Vol 15 (1) ◽  
pp. 33-38 ◽  
Author(s):  
M HIROUCHI ◽  
R KUWANO ◽  
K TAKASHI ◽  
T YASUO ◽  
K KURIYAMA

2018 ◽  
Vol 6 (3) ◽  
pp. 85 ◽  
Author(s):  
Tamás Marik ◽  
Chetna Tyagi ◽  
Gordana Racić ◽  
Dávid Rakk ◽  
András Szekeres ◽  
...  

Trichoderma koningiopsis and T. gamsii belong to clade Viride of Trichoderma, the largest and most diverse group of this genus. They produce a wide range of bioactive secondary metabolites, including peptaibols with antibacterial, antifungal, and antiviral properties. The unusual amino acid residues of peptaibols, i.e., α-aminoisobutyric acid (Aib), isovaline (Iva), and the C-terminal 1,2-amino alcohol make them unique among peptides. In this study, the peptaibiomes of T. koningiopsis and T. gamsii were investigated by HPLC-ESI-MS. The examined strains appeared to produce 19-residue peptaibols, most of which are unknown from literature, but their amino acid sequences are similar to those of trikoningins, tricholongins, trichostrigocins, trichorzianins, and trichorzins. A new group of peptaibols detected in T. koningiopsis are described here under the name “Koningiopsin”. Trikoningin KA V, the closest peptaibol compound to the peptaibols produced by these two strains, was selected for structural investigation by short MD simulation, which revealed that many residues show high preference for left handed helix formation. The bioactivity of the peptaibol mixtures produced by T. koningiopsis and T. gamsii was tested on agar plates against bacteria, yeasts, and filamentous fungi. The results revealed characteristic differences in bioactivities towards the different groups of target microorganisms, which can be explained with the differences in their cell wall structures.


2001 ◽  
Vol 67 (7) ◽  
pp. 3064-3070 ◽  
Author(s):  
Hiroaki Motoyama ◽  
Hiroshi Yano ◽  
Yoko Terasaki ◽  
Hideharu Anazawa

ABSTRACT The dapA gene, encoding dihydrodipicolinate synthase (DDPS) partially desensitized to inhibition by l-lysine, was cloned from an l-threonine- andl-lysine-coproducing mutant of the obligate methylotrophMethylobacillus glycogenes DHL122 by complementation of the nutritional requirement of an Escherichia coli dapAmutant. Introduction of the dapA gene into DHL122 and AL119, which is the parent of DHL122 and an l-threonine producing mutant, elevated the specific activity of DDPS 20-fold andl-lysine production 2- to 3-fold with concomitant reduction of l-threonine in test tube cultures. AL119 containing thedapA gene produced 8 g of l-lysine per liter in a 5-liter jar fermentor from methanol as a substrate. Analysis of the nucleotide sequence of the dapA gene shows that it encodes a peptide with an M r of 30,664 and that the encoded amino acid sequence is extensively homologous to those of other organisms. In order to study the mutation that occurred in DHL122, the dapA genes of the wild type and AL119 were cloned and sequenced. Comparison of the nucleotide sequences of the dapA genes revealed that the amino acid at residue 88 was F in DHL122 whereas it was L in the wild type and AL119, suggesting that this amino acid alteration that occurred in DHL122 caused the partial desensitization of DDPS to the inhibition byl-lysine. The similarity in the amino acid sequences of DDPS in M. glycogenes and other organisms suggests that the mutation of the dapA gene in DHL122 is located in the region concerned with interaction of the allosteric effector,l-lysine.


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