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PubMed2005

Investigation of nu(N-H) and nu(C-N) stretching modes of propylamine (C3H7NH2) in a binary system C3H7NH2 + CH3OH via concentration dependent Raman study and ab initio calculations.

Raman spectra of propylamine (C3H7NH2) and its binary mixtures, C3H7NH2 + CH3OH with varying mole fractions of the reference system, C3H7NH2, C were recorded in two widely apart wavenumber regions, 3100-3600 cm(-1) and 1225-1325 cm(-1). In the former region, the two Raman bands at approximately 3305 and approximately 3326 cm(-1), obtained after the line shape analysis, which were assigned to symmetric nu(N-H) and anti-symmetric nu(N-H) stretching modes, respectively, show a downshift upon dilution. However, whereas the nu(N-H) anti-symmetric mode shows a shift of 18.6 cm(-1), the nu(N-H) symmetric mode shows a much smaller shift (5.7 cm(-1)) between neat liquid and high dilution, C = 0.1. This aspect has been explained using the optimized geometries calculated employing ab initio theory (MP2 level) for the neat C3H7NH2 and its different hydrogen-bonded complexes. The linewidth versus concentration plot for the nu(N-H) anti-symmetric stretching mode, however exhibits a distinct maxima at C = 0.4, which has been explained as a slight departure from the concentration fluctuation model. In the latter region, a symmetric peak is observed, which corresponds to nu(C-N) stretching mode, which shows an upshift upon dilution and an almost linear concentration dependence. This has also been explained in terms of the parameters obtained from the optimized geometries of the different hydrogen-bonded complexes.

Carbon↗
PubMed2003

New propylamine oligopyrrole carboxamides linked to a heterocyclic or anthraquinone system: synthesis, DNA binding, topoisomerase I inhibition and cytotoxicity.

Continuing our studies on combilexines, compounds consisting of a DNA intercalator linked to a minor groove ligand, new results are presented. The synthesis of a series of new propylamine oligopyrrole carboxamides closely related to netropsin and distamycin A, linked to a heterocyclic or anthraquinone system is reported. The cytotoxic activity in vitro, the DNA binding characteristics and the inhibition of the topoisomerase I of the compounds were studied in order to explain the biological mechanism of action of these new potential combilexines. Some of the synthesised compounds showed cytotoxic activity against human tumour cell lines, as well as DNA binding and topoisomerase I inhibiting properties.

Animals↗
PubMed1991

Synthesis and selective class III antiarrhythmic activity of novel N-heteroaralkyl-substituted 1-(aryloxy)-2-propanolamine and related propylamine derivatives.

The synthesis and biological evaluation of a series of novel 1-(aryloxy)-2-propanolamines and several related deshydroxy analogues are described. Compounds 4-29 were prepared and investigated for their class III electrophysiological activity in isolated canine Purkinje fibers and in anesthetized open-chest dogs. None of these compounds showed any class I activity. On the basis of the in vitro data, structure-activity relationships for the series are discussed. Two compounds, N-[4-[2-hydroxy-3-[methyl(2-quinolinylmethyl)amino] propoxy]phenyl]methanesulfonamide (12,WAY-123,223) and N-[2-[[methyl[3-[4-[(methylsulfonyl)amino]phenoxy]propyl] amino]methyl]-6-quinolinyl]-methanesulfonamide (24, WAY-125,971) were identified and characterized as potent and specific class III antiarrhythmic agents in vitro and in vivo. Compound 12 was found to be orally bioavailable, to produce large increases of ventricular fibrillation threshold (VFT), and, in some instances, to restore sinus rhythm from ventricular fibrillation in anesthetized open-chest dogs at a dose of 5 mg/kg (iv). The enantiomers of 12 (i.e., 13 and 14) were synthesized and were found to exhibit similar electrophysiological effects in the Purkinje fiber screen. Compound 24, a propylamine analogue with potency and efficacy comparable to those of UK-68798 (2) and E-4031 (3), was studied in voltage-clamp experiments (isolated cat myocytes) and was found to be a potent and specific blocker of the delayed rectifier potassium current (IK).

Animals↗
PubMed1996

Identification of the cytochrome P450 isozymes involved in the metabolism of N-nitrosodipropyl-,N-nitrosodibutyl- and N-nitroso-n-butyl-n-propylamine.

The metabolism of N-nitrosodipropylamine (NDPA), N-nitrosodibutylamine (NDBA) and N-nitroso-n-butyl-n-propylamine (NBPA) was investigated in vitro using liver microsomes and purified isoforms of cytochrome P450 in a reconstituted system. Liver microsomes were prepared from rats pretreated with phenobarbital (PB), pyridine (PYR), beta-naphthoflavone (BNF), butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), clofibrate (CLO) or from untreated rats. The purified cytochrome P450s used in the reconstituted system were rat 1A1 and 2B1 and rabbit 2E1. The rates of metabolism and the product profiles for NDPA, NDBA and NBPA changed significantly depending on the pretreatment of the rats or the identity of the purified cytochrome P450 isoforms. Induction by PB dramatically increased cleavage of NDPA, NDBA and NBPA at C-N bonds, leading to substantial increases in formation of the respective aldehydes and the overall metabolic rates. Microsomes from PYR-pretreated rats exhibited increased activities for formation of formaldehyde and propionaldehyde from NDPA and NBPA. Microsomes from BHT-pretreated rats showed a slight increase in activity for N-dealkylation of NDBA and BNPA. Treatment with BHA decreased the overall metabolism of NDBA, but slightly increased N-dealkylation of NBPA. Microsomal metabolism of NDPA, NDBA and NBPA was decreased by pretreatment with BNF and CLO. Results from studies using the reconstituted system with purified cytochrome P450 isoforms demonstrated that cytochrome P450 2B1 specifically catalyzed alpha-hydroxylation of these three long chain nitrosamines with high activity. Cytochrome P450 2E1 catalyzed formation of formaldehyde and propionaldehyde from NDPA and NBPA, but did not catalyze formation of acetaldehyde or butyraldehyde. Cytochrome P450 1A1 exhibited no activity for metabolism of NDPA, NDBA and NBPA. The contributions of cytochrome P450 2B1 and 2E1 to N-dealkylation reactions were determined using inhibitory monoclonal antibodies (mAb). With microsomes from PB-pretreated rats, inhibition by mAb-2B1 indicated a 62% contribution by cytochrome P450 2B1 to debutylation of NDBA and 65% to depropylation of NDPA. In microsomes from PYR-pretreated rats inhibition by mAbs also showed a role for cytochrome P450 2E1 in depropylation of NDPA. These studies provide a better understanding of the role of various forms of cytochrome P450 in metabolic activation of these long chain N-nitrosodialkylamines to potentially toxic, mutagenic and carcinogenic intermediates.

Animals↗
PubMed1975

Metabolism of n-propylamine, isopropylamine, and 1,3-propane diamine by Mycobacterium convolutum.

Mycobacterium convolutum strain NPA-1 can utilize n-propylamine (NPA), isopropylamine (IPA), and 1,3-propane diamine (PD) as sole source of carbon, nitrogen, and energy. Enzyme assays, fatty acid profiles, and 14CO2 incorporation experiments indicate that NPA is deaminated to propionate and further metabolized via the methylmalonyl succinate pathway, and IPA and PD were metabolized (after deamination) through a C2 + C1 cleavage. An inducible amine dehydrogenase was present in cell extracts after growth on the three amines. Polyacrylamide gel electrophoresis of cell extracts from NPA- and IPA-grown cells yielded one major band of amine dehydrogenase activity. When extracts of NPA-grown cells were assayed with NPA, IPA, or PD as substrate, the relative position of the major band on gel electrophoresis was equivalent. Similar results were obtained with extracts prepared from IPA-grown cells. Sephadex G-100 chromatography also indicated one major peak of activity. This suggests that one enzyme of broad specificity is involved in deamination of IPA, NPA, and PD. IPA-grown cells utilized NPA readily, whereas NPA-grown cells could not utilize IPA without lag. Since amine dehydrogenase activity was present in extracts of cells after growth on either substrate, this lag was probably due to the inability to transport IPA without an induction period. The molecular weight of the amine dehydrogenase was approximately 38,500 as determined by gel filtration.

1-Propanol↗
PubMed1980

Preparation of colony stimulating activity from human leukemic urine: hydrophobic chromatography on propylamine-agarose.

Urinary colony stimulating factor (CSF) from human leukemic urine is retained on propylamine-agarose hydrophobic chromatography; about 70% of total activity is eluted by the addition of 1 M NaCl with significant increase in specific activity. Incomplete binding of urinary CSF to this resin further confirm that biological activity is a heterogeneous pool of different molecular species. Analysis of the macro- and microscopic composition of colonies indicates that CSF resulting from this purification step maintains the ability to stimulate both granulocytic and macrophage progenitors.

Chromatography, Agarose↗
PubMed1996

N,N'-bis[3,3'-(dimethylamino)propylamine]-3,4,9, 10-perylenetetracarboxylic diimide, a dicationic perylene dye for rapid precipitation and quantitation of trace amounts of DNA.

A novel dicationic dye with a polycyclic aromatic perylene core and flexible cationic side chains- N,N'-bis[3, 3'-(dimethylamino)propylamine]-3,4,9,10-perylenetetracarboxylic diimide-termed "DAPER," was synthesized and characterized. The dye appears to exist in a highly stacked form in aqueous solution. DAPER precipitates extremely low concentrations of DNA very rapidly, efficiently, and with a stoichiometry of one tightly bound dye per DNA base pair, corresponding to a neutral complex. Precipitation may occur due to side-by-side association between the polyanionic DNA helix and polycationic dye stacks. DNA precipitation by DAPER is less sensitive to DNA concentration and length, and prevailing salt concentrations, than precipitation with ethanol or propanol. DAPER can be quantitatively extracted from DNA into a standard phenol:chloroform mixture under slightly alkaline conditions. The recovered DNA is suitable for treatment with enzymes typically used in DNA sequencing procedures. The amount of DNA precipitated is accurately determined by visible absorption or fluorescence spectroscopic analyses of the phenol:chloroform extracts. Several samples of DNA can be precipitated, recovered, and quantitated in about 1 h using standard microscale procedures and equipment. The unique qualities of DAPER provide the basis for a very sensitive, rapid, and versatile method for simultaneous precipitation and quantitation of microgram and submicrogram amounts of DNA.

1-Propanol↗
PubMed1978

Microsomal metabolism of N-nitrosodi-n-propylamine: formation of products resulting from alpha- and beta-oxidation.

We have identified propionaldehyde, n-propranolo, isopropanol and N-nitroso-2-hydroxy-propylpropylamine following incubation of N-nitrosodi-n-propylamine with a microsomal fraction from rat liver. Based on the yields of the various products, we have shown that beta-oxidation occurs at about 15% of the level of alpha-oxidation, beta- as well as alpha-oxidation was shown to be carried out by the microsomal mixed function oxidase system. N-nitroso-2-hydroxy-propylpropylamine is further oxidized by the microsomal preparation to yield N-nitroso-2-oxopropylpropylamine.

Animals↗
PubMed1998

2-Mercapto-propylamine: radiopharmacology in mice, pharmacokinetic studies in mice and in rats, mutagenicity and differential distribution between tissues and EMT6 tumour in mice.

Radiopharmacological studies conducted with 2-mercapto-propylamine (2MPA), a methylated derivative of cysteamine, indicated a good efficiency in whole body irradiated mice as observed over a period of 9 months. Its efficacy was also checked for supralethal irradiations of restricted body parts: in the brain and the rectum. The diffusion of 14C-labelled 2MPA was assessed by an autoradiographic study and measurement of its distribution in the main organs in mice. 2MPA penetrated the blood brain barrier but concentrated preferentially in the liver, kidney and skin. Fixation on plasmatic proteins was much lower in rats than in mice but urinary and faecal eliminations were of the same order for the two species. An important biliary excretion of 2MPA or its metabolites in rats combined with their lack in the faeces underlies an entero-hepatic cycle. A differential diffusion of 2MPA between normal tissues in mice and EMT6 tumours was clearly revealed by autoradiographic observations. The ability of 2MPA to trap 2,2'-diphenyl 1-picryl hydrazyl, an organic free radical, was checked by in vitro studies. Its performance indicated that 2MPA acted at least as a free radical scavenger. Ames test demonstrated that 2MPA whatever the dose employed was not a mutagenic agent. Pharmacological and pharmacokinetical observations provided a better understanding of the activity of this drug.

Animals↗
PubMed1999

N-Nitrosodi-n-propylamine induces organ specific mutagenesis with specific expression times in lacZ transgenic mice.

The mutagenic and clastogenic effects of N-nitrosodi-n-propylamine (NDPA) in lacZ transgenic mice (MutaMouse) were investigated as a part of the second collaborative study of the transgenic mouse mutation assay by a subgroup of the Mammalian Mutagenesis Study Group, a suborganization of the Environmental Mutagen Society of Japan. Male MutaMouse mice were administered NDPA intraperitoneally at a dose of 250 mg/kg, which is half of the LD(50) of the compound. The clastogenicity of NDPA was examined by the peripheral blood micronucleus test just before and at 24, 48 and 72 h after the treatment. The mutant frequencies in the bone marrow, liver, lung, kidney and urinary bladder were examined by the positive selection method for lacZ kidney. These findings demonstrate that NDPA induces organ-specific mutagenesis with specific expression times, and that the mutagenicity of NDPA in lacZ transgenic mice is consistent with its carcinogenicity.

Animals↗
PubMed1996

Novel Dendritic alpha-Sialosides: Synthesis of Glycodendrimers Based on a 3,3'-Iminobis(propylamine) Core.

The cluster or multivalent effect has been recognized as an effective means by which to increase binding interactions between carbohydrates and proteins. In fact, it has been demonstrated that sialylated multibranched L-lysine dendrimers were potent inhibitors of hemagglutination of human erythrocytes by Influenza viruses. In a continuation of these studies, the synthesis of novel glycodendrimers with even valencies from 2 to 16 and ending with equidistant thiosialoside residues is described. These symmetrical dendrimers were more readily characterized by standard NMR spectral techniques than previously reported nonsymmetrical dendrimers of this general type. The synthesis of the dendritic core was based on the regioselective protection of the primary amines of 3,3'-iminobis(propylamine) (4) using benzyl cyanoformate. The resulting secondary amine 5 was alkylated with tert-butyl bromoacetate to provide divalent core structure 6 with Cbz protected amines and acid protected tert-butyl ester. Sequential deprotection by trifluoroacetolysis or hydrogenation afforded acid 7 or diamine 8 as key precursors, respectively. The two fragments were coupled using HOBt/DIC strategy to provide Cbz-protected dendrimers with valencies of 2, 4, 8, and 16 in the first, second, third, and fourth generations, respectively, in reasonable to good yields (42-82%). Cbz-protected precursors were efficiently transformed into N-chloroacetylated dendrimers by hydrogenolysis and treatment of the resulting amines with chloroacetic anhydride (82-91%). N-Chloroacetylated dendrimers were then treated with an excess of 2-thiosialic acid derivative 3 to give fully protected sialodendrimers in 76-96% yields. Deprotection of sialodendrimers under Zemplén conditions followed by methyl ester saponification and purification by gel permeation chromatography afforded symmetrical dendritic alpha-thiosialosides 21, 23, 25, and 27 in fair yields (47-58%). These novel sialodendrimers, in keeping with their design, are currently being evaluated as inhibitors of human erythrocyte hemagglutination by Influenza viruses.

Journal Article↗
PubMed2003

Facile synthesis of optically pure 1,2-diaryl (and 1-Alkyl-2-aryl) ethyl and propylamines.

A concise high-yielding route to synthetically useful 1,2-diaryl (and 1-alkyl-2-aryl) ethyl and propylamines in high enantiomeric purity is described. The key step of this route is the completely stereoselective addition of lithium (R)-ortho-(p-toluenesulfinyl)benzylic carbanions to (S)-N-p-toluenesulfinylimines, which takes place in very high or quantitative yields. N-Desulfinylation and C-desulfinylation of the resulting adducts can be achieved with no loss of optical purity employing conventional methods (TFA and Raney-Ni, respectively).

Journal Article↗
PubMed1980

Role of propylamine transferases in hormone-induced stimulation of polyamine biosynthesis.

The effect of various hormones on the activities of the four enzymes engaged with the biosynthesis of the polyamines has been investigated in the rat. Human choriogonadotropin induced a dramatic, yet transient, stimulation of l-ornithine decarboxylase (EC 4.1.1.17) activity in rat ovary, with no or only marginal changes in the activities of S-adenosyl-l-methionine decarboxylase (EC 4.1.1.50), spermidine synthase (aminopropyltransferase; EC 2.5.1.16) or spermine synthase. A single injection of oestradiol into immature rats maximally induced uterine ornithine decarboxylase at 4h after the injection. This early stimulation of ornithine decarboxylase activity was accompanied by a distinct enhancement of adenosylmethionine decarboxylase activity and a decrease in the activities of spermidine synthase and spermine synthase. In the seminal vesicle of castrated rats, testosterone treatment elicited a striking and persistent stimulation of ornithine decarboxylase and adenosylmethionine decarboxylase activities. The activity of spermidine synthase likewise rapidly increased between the first and the second day after the commencement of the hormone treatment, whereas the activity of spermine synthase remained virtually unchanged during the whole period of observation. Testosterone-induced changes in polyamine formation in the ventral prostate were comparable with those found in the seminal vesicle, with the possible exception of a more pronounced stimulation of spermidine synthase activity. It thus appears that an enhancement in one or both of the propylamine transferase (aminopropyltransferase) activities in response to hormone administration is an indicator of hormone-dependent growth (uterus and the male accessory sexual glands), and is not necessarily associated with non-proliferative hormonal responses, such as gonadotropin-induced luteinization of the ovarian tissue.

Adenosylmethionine Decarboxylase↗
PubMed2001

Metabolism of the beta-oxidized intermediates of N-nitrosodi-n-propylamine: N-nitroso-beta-hydroxypropylpropylamine and N-nitroso-beta-oxopropylpropylamine.

The rat liver carcinogen N-nitrosodi-n-propylamine (NDPA) is metabolized to a propylating and methylating species in vivo. Metabolism to a methylating species is believed to require an initial hydroxylation by cytochrome P450s (P450s) to N-nitroso-beta-hydroxypropylpropylamine (NHPPA), which is oxidized to N-nitroso-beta-oxopropylpropylamine (NOPPA), followed by a P450-mediated depropylation to beta-oxopropyldiazotate, which non-enzymatically breaks down to the methylating agent. Purified rat liver P450 2B1 and rabbit liver 2E1 in the reconstituted system and liver microsomes from phenobarbital (PB) and pyridine (Pyr) treated rats readily metabolized NOPPA to a methylating species as determined by the in vitro formation of 7-methylguanine (m7Gua) in DNA. Exposure of cells derived from the human liver epithelium transfected with human 2E1 (T5-2E1) to NOPPA resulted in the formation of m7Gua DNA adducts and a dose dependent toxicity. In vitro incubation of NHPPA with microsomes from PB, Pyr and non-treated (NT) rats and a human microsomal sample also resulted in m7Gua formation. P450s 2B1 and 2E1 oxidized NHPPA to NOPPA, forming 16.5 +/- 3.1 and 20.0 +/- 4.4 pmol NOPPA/pmol P450 in 1 h, respectively. Rat liver cytosol, in the presence of NAD+, oxidized NHPPA to NOPPA at a rate of 13.7 +/- 3.0 pmol/min/mg protein while microsomes from NT rats catalyzed this reaction at 95.6 +/- 16.5 pmol/min/mg protein. Cells derived from hamster lung tissue (V79 control) and T5-neo cells oxidized NHPPA to NOPPA. This oxidation was about 15 fold higher in T5-2E1 or V79 cells transfected with human 2E1 or rat 2B1, respectively. The results are consistent with the putative sequential oxidation pathway and suggest that, at the concentrations tested, oxidation of NHPPA to NOPPA may be predominantly mediated by cytochrome P450s. In addition, it appears that rabbit, rat and human P450 2E1 can catalyze both oxidations.

Animals↗
PubMed1985

Mechanism of DNA methylation by N-nitroso(2-oxopropyl)propylamine.

Using an in vitro assay system for measuring 7-methylguanine formation in DNA, it was demonstrated that N-nitroso(2-oxopropyl)propylamine (NOPPA) is converted into a methylating agent by a microsomal, cytochrome P-450 dependent mixed function oxidase from rat liver. Formation of propionaldehyde, but not formaldehyde, in this assay system, indicated that a single alpha-oxidation reaction on the propyl side chain of NOPPA leads to the formation of a methylating agent. A mechanism for this reaction is proposed.

Animals↗
PubMed1988

Comparative study on the carcinogenicity of N-nitrosodiethylamine, N-nitrosodimethylamine, N-nitrosomorpholine, N-nitrosopyrrolidine and N-nitrosodi-n-propylamine to the lung of Syrian golden hamsters following intermittent instillations to the trachea.

N-Nitrosodiethylamine (NDEA), N-nitrosodimethylamine (NDMA), N-nitrosomorpholine (NMOR), N-nitrosopyrrolidine (NPYR) and N-nitrosodi-n-propylamine (NDPA) were instilled into the lungs of male Syrian golden hamsters by intratracheal instillations once a week for 15 weeks. The total doses given were 1.5 mg of each drug. As a control, hamsters were treated with the vehicle, phosphate buffer solution. During the total lifespan, tumor incidence rates in the respiratory organs were 100% in the NDEA group, 6% in the NDMA group, 43% in the NMOR group, 0% in the NPYR group, 72% in the NDPA group and 4% in the control group. The incidence rates in the liver were 19% in the NDMA group and 4% in the NPYR group. No liver tumors developed in the other groups. The carcinogenic potencies of these N-nitroso compounds to the respiratory organs was provisionally estimated to be in the following order: NDEA greater than NDPA greater than NMOR greater than NDMA = NPYR, at the 1.5 mg dosage level. However, the difference in the rates of tumor incidence between the NDMA or NPYR group and the control group was not significant.

Adenoma↗
PubMed1984

Propylamine transferases in chinese cabbage leaves.

We have found spermidine synthase and spermine synthase activities in extracts of leaves of Chinese cabbage (Brassica pekinensis var. Pak Choy) and have developed an assay of the former in crude extracts. The method is based on the transfer of the propylamine moiety of decarboxylated S-adenosylmethionine to labeled putrescine, followed by ion-exchange separation of the labeled amine substrate and product, which are then converted to the 5-dimethylamino-1-napthalene sulfonyl (dansyl) derivatives and further purified and identified by thin layer chromatography. The specific radioactivity of putrescine present in the reaction mixture is determined, as is the radioactivity present in dansyl spermidine. The enzyme is also present in extracts of spinach leaves.Spermidine synthase has been purified about 160-fold from Chinese cabbage leaves. After partial purification, a rapid coupled enzymic assay has been used to study various properties of the enzyme. The plant enzyme shows maximum activity at pH 8.8 in glycine-NaOH buffer and has a molecular weight of 81,000. The K(m) values for decarboxylated S-adenosylmethionine and putrescine are 6.7 and 32 micromolar, respectively. The enzyme activity is inhibited strongly by dicyclohexylamine, cyclohexylamine, and S-adenosyl-3-thio-1, 8-diaminoctane. Of these, dicyclohexylamine is the most potent inhibitor with an I(50) at 0.24 micromolar.

Journal Article↗
PubMed1992

Effect of temperature on the propylamine transferase from Sulfolobus solfataricus, an extreme thermophilic archaebacterium. 1. Conformational behavior of the oligomeric enzyme in solution.

The effect of temperature on the molecular structure of propylamine transferase from Sulfolobus solfataricus has been investigated. Sulfolobus solfataricus is an extreme thermophilic archaebacterium with an optimum living condition at 90 degrees C. The enzyme is an oligomeric (trimer) protein of molecular mass 112 kDa. The frictional ratio for the native protein suggests an irregularly shaped compact globular structure. The protein matrix is well organized as suggested by far ultraviolet circular dichroism at 25 degrees C (18% alpha helix, 43% beta structure, 19% beta bends and 20% unordered: root mean square = 7). Structural effects of temperature were investigated over 25-85 degrees C. The protein retains its quaternary structure in this temperature range. A highly reversible subtle conformational transition was detected by numerous structure-dependent techniques over 40-50 degrees C, with a midpoint centered at 45 degrees C. Functional data also support this view. In fact, two enzyme forms, characterized by different catalytic properties, are present in solution. The Arrhenius plot suggests the occurrence of two different activation-energy-dependent processes, one at a temperature higher and one at a temperature lower than 45 degrees C. The transition has been considered as a molecular switch between two protein populations at equilibrium with different functional and structural properties, temperature modulated. A physiological role for the molecular switch has also been postulated. The protein also shows some subtle and reversible spectroscopic changes around 75 degrees C. The molecular basis of the thermophilic nature of this enzyme seems to reside in its capability to dynamically couple catalytic and structural events to the thermal properties of the ambient medium.

Amino Acids↗