Structural basis for thermostability of beta-glycosidase from the thermophilic eubacterium Thermus nonproteolyticus HG102

Structural insights and functional characterization of a novel β-glucosidase derived from Thermotoga profunda

β-Glucosidase is a crucial cellulase, as its activity determines the efficiency of cellulose hydrolysis into glucose. This study addresses the functional and structural characteristics of Thermotoga profunda β-glucosidase (Tp-BGL). Tp-BGL exhibited a Km of 0.3798 mM for p-nitrophenyl-β-d-glucopyranoside (pNPGlc) and 4.44 mM for cellobiose, with kcat/Km of 1211.16 and 4.18 s-1 mM-1, respectively. In addition, Tp-BGL showed significant pH adaptability and thermal stability, with a Tm of 85.7 °C and retaining >90 % of its activity after incubation at 80 °C for 90 min. The crystal structure of Tp-BGL was resolved at 1.95 Å resolution, and reveals a typical TIM barrel structure. Comparative structural analysis highlighted that the major distinction between Tp-BGL and the other glucosidases lies in their loop regions.

Structural studies of β-glucosidase from the thermophilic bacterium Caldicellulosiruptor saccharolyticus

β-Glucosidase from the thermophilic bacterium Caldicellulosiruptor saccharolyticus (Bgl1) has been denoted as having an attractive catalytic profile for various industrial applications. Bgl1 catalyses the final step of in the decomposition of cellulose, an unbranched glucose polymer that has attracted the attention of researchers in recent years as it is the most abundant renewable source of reduced carbon in the biosphere. With the aim of enhancing the thermostability of Bgl1 for a broad spectrum of biotechnological processes, it has been subjected to structural studies. Crystal structures of Bgl1 and its complex with glucose were determined at 1.47 and 1.95 Å resolution, respectively. Bgl1 is a member of glycosyl hydrolase family 1 (GH1 superfamily, EC 3.2.1.21) and the results showed that the 3D structure of Bgl1 follows the overall architecture of the GH1 family, with a classical (β/α)8 TIM-barrel fold. Comparisons of Bgl1 with sequence or structural homologues of β-glucosidase reveal quite similar structures but also unique structural features in Bgl1 with plausible functional roles.

Structural determinants of cold activity and glucose tolerance of a family 1 glycoside hydrolase (GH1) from Antarctic Marinomonas sp. ef1

Cold-active enzymes support life at low temperatures due to their ability to maintain high activity in the cold and can be useful in several biotechnological applications. Although information on the mechanisms of enzyme cold adaptation is still too limited to devise general rules, it appears that very diverse structural and functional changes are exploited in different protein families and within the same family. In this context, we studied the cold adaptation mechanism and the functional properties of a member of the glycoside hydrolase family 1 (GH1) from the Antarctic bacterium Marinomonas sp. ef1. This enzyme exhibits all typical functional hallmarks of cold adaptation, including high catalytic activity at 5 °C, broad substrate specificity, low thermal stability, and higher lability of the active site compared to the overall structure. Analysis of the here-reported crystal structure (1.8 Å resolution) and molecular dynamics simulations suggest that cold activity and thermolability may be due to a flexible region around the active site (residues 298-331), whereas the dynamic behavior of loops flanking the active site (residues 47-61 and 407-413) may favor enzyme-substrate interactions at the optimal temperature of catalysis (Topt) by tethering together protein regions lining the active site. Stapling of the N-terminus onto the surface of the β-barrel is suggested to partly counterbalance protein flexibility, thus providing a stabilizing effect. The tolerance of the enzyme to glucose and galactose is accounted for by the presence of a "gatekeeping" hydrophobic residue (Leu178), located at the entrance of the active site.

Trends in the development and current perspective of thermostable bacterial hemicellulases with their industrial endeavors: A review

Hemicellulases are enzymes that hydrolyze hemicelluloses, common polysaccharides in nature. Thermophilic hemicellulases, derived from microbial strains, are extensively studied as natural biofuel sources due to the complex structure of hemicelluloses. Recent research aims to elucidate the catalytic principles, mechanisms and specificity of hemicellulases through investigations into their high-temperature stability and structural features, which have applications in biotechnology and industry. This review article targets to serve as a comprehensive resource, highlighting the significant progress in the field and emphasizing the vital role of thermophilic hemicellulases in eco-friendly catalysis. The primary goal is to improve the reliability of hemicellulase enzymes obtained from thermophilic bacterial strains. Additionally, with their ability to break down lignocellulosic materials, hemicellulases hold immense potential for biofuel production. Despite their potential, the commercial viability is hindered by their high enzyme costs, necessitating the development of efficient bioprocesses involving waste pretreatment with microbial consortia to overcome this challenge.

Producing natural vanilla extract from green vanilla beans using a β-glucosidase from Alicyclobacillus acidiphilus

Current methods for the production of natural vanilla extract are long and tedious, and the efficiency of the vanillin extraction is usually conditioned by different factors during the traditional curing process (temperatures and weather conditions). As an important fraction of vanillin is present in the form of glucovanillin in green beans, endogenous β-glucosidases contribute to its hydrolysis; however, these enzymes lose efficiency during the curing process. The use of extremophilic organisms as a source of an appropriate exogenous enzyme can offer a valid alternative when producing natural vanillin. Here, a β-glucosidase from the thermo-acidophilic organism Alicyclobacillus acidiphilus (AacGH1) was cloned, expressed in E. coli BL21, and fully characterized in respect to both function and crystal structure. Notably, AacGH1 was stable at a temperature up to 50 °C and exhibited good tolerance to glucose, fructose and organic solvents, in particular it maintained full activity in the presence of up to 20 % (v/v) ethanol. The enzyme was then successfully applied to an ethanol-water (20 % (v/v)) extract of green vanilla beans and the complete hydrolysis of glucovanillin (1.7 mM) to vanillin, and other flavour compounds commonly found in vanilla, was achieved using 0.5 mg/mL of enzyme in just 15 min at 30 °C.

Engineering novel S-glycosidase activity into extremo-adapted β-glucosidase by rational design

The breakdown of sulphur glycosidic bonds in thioglycosides can produce isothiocyanate, a chemoprotective agent linked to the prevention of cancers; however, only a handful of enzymes have been identified that are k0nown to catalyse this reaction. Structural studies of the myrosinase enzyme, which is capable of hydrolysing the thioglycosidic bond, have identified residues that may play important roles in sulphur bond specific activity. Using rational design, two extremo-adapted β-glycosidases from the species Thermus nonproteolyticus (TnoGH1) and Halothermothrix orenii (HorGH1) were engineered towards thioglycoside substrates. Twelve variants, six for TnoGH1and six for HorGH1, were assayed for activity. Remarkable enhancement of the specificity (k_cat/K_M) of TnoGH1 and HorGH1 towards β-thioglycoside was observed in the single mutants TnoGH1-V287R (2500 M^-1 s^-1) and HorGH1-M229R (13,260 M^-1 s^-1) which showed a 3-fold increase with no loss in turnover rate when compared with the wild-type enzymes. Thus, the role of arginine is key to induce β-thioglycosidase activity. Thorough kinetic investigation of the different mutants has shed light on the mechanism of β-glycosidases when acting on the native substrate.Key Points •Key residues were identified in the active site of Brevicoryne brassicae myrosinase. •Rationally designed mutations were introduced into two extremo-adapted β-glycosidases. •β-glycosidases mutants exhibited improved activity against thioglycosidic bonds. •The mutation to arginine in the active site yielded the best variant.

Biochemical Characterization and Low-Resolution SAXS Molecular Envelope of GH1 β-Glycosidase from Saccharophagus degradans

The marine bacteria Saccharophagus degradans (also known as Microbulbifer degradans), are rod-shaped and gram-negative motile γ-proteobacteria, capable of both degrading a variety of complex polysaccharides and fermenting monosaccharides into ethanol. In order to obtain insights into structure-function relationships of the enzymes, involved in these biochemical processes, we characterized a S. degradans β-glycosidase from glycoside hydrolase family 1 (SdBgl1B). SdBgl1B has the optimum pH of 6.0 and a melting temperature T _m of approximately 50 °C. The enzyme has high specificity toward short D-glucose saccharides with β-linkages with the following preferences β-1,3 > β-1,4 ≫ β-1,6. The enzyme kinetic parameters, obtained using artificial substrates p-β-NPGlu and p-β-NPFuc and also the disaccharides cellobiose, gentiobiose and laminaribiose, revealed SdBgl1B preference for p-β-NPGlu and laminaribiose, which indicates its affinity for glucose and also preference for β-1,3 linkages. To better understand structural basis of the enzyme activity its 3D model was built and analysed. The 3D model fits well into the experimentally retrieved low-resolution SAXS-based envelope of the enzyme, confirming monomeric state of SdBgl1B in solution.

Specific amino acids responsible for the cold adaptedness of Micrococcus antarcticus β-glucosidase BglU

Psychrophilic enzymes display efficient activity at moderate or low temperatures (4-25 °C) and are therefore of great interest in biotechnological industries. We previously examined the crystal structure of BglU, a psychrophilic β-glucosidase from the bacterium Micrococcus antarcticus, at 2.2 Å resolution. In structural comparison and sequence alignment with mesophilic (BglB) and thermophilic (GlyTn) counterpart enzymes, BglU showed much lower contents of Pro residue and of charged amino acids (particularly positively charged) on the accessible surface area. In the present study, we investigated the roles of specific amino acid residues in the cold adaptedness of BglU. Mutagenesis assays showed that the mutations G261R and Q448P increased optimal temperature (from 25 to 40-45 °C) at the expense of low-temperature activity, but had no notable effects on maximal activity or heat lability. Mutations A368P, T383P, and A389E significantly increased optimal temperature (from 25 to 35-40 °C) and maximal activity (~1.5-fold relative to BglU). Thermostability of A368P and A389E increased slightly at 30 °C. Mutations K163P, N228P, and H301A greatly reduced enzymatic activity-almost completely in the case of H301A. Low contents of Pro, Arg, and Glu are important factors contributing to BglU's psychrophilic properties. Our findings will be useful in structure-based engineering of psychrophilic enzymes and in production of mutants suitable for a variety of industrial processes (e.g., food production, sewage treatment) at cold or moderate temperatures.

Molecular Structural Basis for the Cold Adaptedness of the Psychrophilic β-Glucosidase BglU in Micrococcus antarcticus

Psychrophilic enzymes play crucial roles in cold adaptation of microbes and provide useful models for studies of protein evolution, folding, and dynamic properties. We examined the crystal structure (2.2-Å resolution) of the psychrophilic β-glucosidase BglU, a member of the glycosyl hydrolase 1 (GH1) enzyme family found in the cold-adapted bacterium Micrococcus antarcticus. Structural comparison and sequence alignment between BglU and its mesophilic and thermophilic counterpart enzymes (BglB and GlyTn, respectively) revealed two notable features distinct to BglU: (i) a unique long-loop L3 (35 versus 7 amino acids in others) involved in substrate binding and (ii) a unique amino acid, His299 (Tyr in others), involved in the stabilization of an ordered water molecule chain. Shortening of loop L3 to 25 amino acids reduced low-temperature catalytic activity, substrate-binding ability, the optimal temperature, and the melting temperature (Tm). Mutation of His299 to Tyr increased the optimal temperature, the Tm, and the catalytic activity. Conversely, mutation of Tyr301 to His in BglB caused a reduction in catalytic activity, thermostability, and the optimal temperature (45 to 35°C). Loop L3 shortening and H299Y substitution jointly restored enzyme activity to the level of BglU, but at moderate temperatures. Our findings indicate that loop L3 controls the level of catalytic activity at low temperatures, residue His299 is responsible for thermolability (particularly heat lability of the active center), and long-loop L3 and His299 are jointly responsible for the psychrophilic properties. The described structural basis for the cold adaptedness of BglU will be helpful for structure-based engineering of new cold-adapted enzymes and for the production of mutants useful in a variety of industrial processes at different temperatures.

Characterization of amygdalin-degrading Lactobacillus species

AIMS

Cyanogenic glycosides are phytotoxic secondary metabolites produced by some crop plants. The aim of this study was to identify lactic acid bacteria (LAB) capable of catabolizing amygdalin, a model cyanogenic glycoside, for use in the biodetoxification of amygdalin-containing foods and feeds.

METHODS AND RESULTS

Amygdalin-catabolizing lactobacilli were characterized using a combination of cultivation-dependent and molecular assays. Lactobacillus paraplantarum and Lactobacillus plantarum grew robustly on amygdalin (Amg(+)), while other LAB species typically failed to catabolize amygdalin (Amg(-)). Interestingly, high concentrations of amygdalin and two of its metabolic derivatives (mandelonitrile and benzaldehyde) inhibited the growth of Lact. plantarum RENO 0093. The differential regulation of genes tentatively involved in cyanohydrin metabolism illustrated that the metabolism of amygdalin- and glucose-grown cultures also differed significantly.

CONCLUSIONS

Amygdalin fermentation was a relatively uncommon phenotype among the LAB and generally limited to strains from the Lact. plantarum group. Phenotype microarrays (PM) enabled strain-level discrimination between closely related strains within a species and suggested that phenotypic differences might affect niche specialization.

SIGNIFICANCE AND IMPACT OF THE STUDY

Amygdalin-degrading lactobacilli with practical application in the biodetoxification of amygdalin were characterized. These strains show potential for use as starter cultures to improve the safety of foods and feeds.

Discovery of two novel β-glucosidases from an Amazon soil metagenomic library

An Amazon soil microbial community metagenomic fosmid library was functionally screened for β-glucosidase activity. Contig analysis of positive clones revealed the presence of two ORFs encoding novel β-glucosidases, AmBGL17 and AmBGL18, from the GH3 and GH1 families, respectively. Both AmBGL17 and AmBGL18 were functionally identified as β-glucosidases. The enzymatic activity of AmBGL17 was further characterized. AmBGL17 was tested with different substrates and showed highest activity on pNPβG substrate with an optimum temperature of 45 °C and an optimum pH of 6. AmBGL17 showed a Vmax of 116 mM s(-1) and Km of 0.30 ± 0.017 mM. This is the first report of β-glucosidases from an Amazon soil microbial community using a metagenomic approach.

In silico characterization of thermostable lipases

Thermostable lipases are of high priority for industrial applications as they are endowed with the capability of carrying out diversified reactions at elevated temperatures. Extremophiles are their potential source. Sequence and structure annotation of thermostable lipases can elucidate evolution of lipases from their mesophilic counterparts with enhanced thermostability hence better industrial potential. Sequence analysis highlighted the conserved residues in bacterial and fungal thermostable lipases. Higher frequency of AXXXA motif and poly Ala residues in lid domain of thermostable Bacillus lipases were distinguishing characteristics. Comparison of amino acid composition among thermostable and mesostable lipases brought into light the role of neutral, charged and aromatic amino acid residues in enhancement of thermostability. Structural annotation of thermostable lipases with that of mesostable lipases revealed some striking features which are increment of gamma turns in thermostable lipases; being first time reported in our paper, longer beta strands, lesser beta-branched residues in helices, increase in charged-neutral hydrogen bonding pair, hydrophobic-hydrophobic contact and differences in the N-cap and C-cap residues of the α helices. Conclusively, it can be stated that subtle changes in the arrangement of amino acid residues in the tertiary structure of lipases contributes to enhanced thermostability.

Thermostable enzymes as biocatalysts in the biofuel industry

Lignocellulose is the most abundant carbohydrate source in nature and represents an ideal renewable energy source. Thermostable enzymes that hydrolyze lignocellulose to its component sugars have significant advantages for improving the conversion rate of biomass over their mesophilic counterparts. We review here the recent literature on the development and use of thermostable enzymes for the depolymerization of lignocellulosic feedstocks for biofuel production. Furthermore, we discuss the protein structure, mechanisms of thermostability, and specific strategies that can be used to improve the thermal stability of lignocellulosic biocatalysts.

Comparative study and mutational analysis of distinctive structural elements of hyperthermophilic enzymes

Comparison of the three-dimensional structure of hyperthermophilic and mesophilic beta-glycosidases shows differences in secondary structure composition. The enzymes from hyperthermophilic archaea have a significantly larger number of beta-strands arranged in supernumerary beta-sheets compared to mesophilic enzymes from bacteria and other organisms. Amino acid replacements designed to alter the structure of the supernumerary beta-strands were introduced by site directed mutagenesis into the sequence encoding the beta-glycosidase from Sulfolobus solfataricus. Most of the replacements caused almost complete loss of activity but some yielded enzyme variants whose activities were affected specifically at higher temperatures. Far-UV CD spectra recorded as a function of temperature for both wild type beta-glycosidase and mutant V349G, one of the mutants with reduced activity at higher temperatures, were similar, showing that the protein structure of the mutant was stable at the highest temperatures assayed. The properties of mutant V349G show a difference between thermostability (stability of the protein structure at high temperatures) and thermophilicity (optimal activity at high temperatures).

The Crystal Structure of Human Cytosolic β-Glucosidase Unravels the Substrate Aglycone Specificity of a Family 1 Glycoside Hydrolase

Human cytosolic beta-glucosidase (hCBG) is a xenobiotic-metabolizing enzyme that hydrolyses certain flavonoid glucosides, with specificity depending on the aglycone moiety, the type of sugar and the linkage between them. In this study, the substrate preference of this enzyme was investigated by mutational analysis, X-ray crystallography and homology modelling. The crystal structure of hCBG was solved by the molecular replacement method and refined at 2.7 A resolution. The main-chain fold of the enzyme belongs to the (beta/alpha)(8) barrel structure, which is common to family 1 glycoside hydrolases. The active site is located at the bottom of a pocket (about 16 A deep) formed by large surface loops, surrounding the C termini of the barrel of beta-strands. As for all the clan of GH-A enzymes, the two catalytic glutamate residues are located on strand 4 (the acid/base Glu165) and on strand 7 (the nucleophile Glu373). Although many features of hCBG were shown to be very similar to previously described enzymes from this family, crucial differences were observed in the surface loops surrounding the aglycone binding site, and these are likely to strongly influence the substrate specificity. The positioning of a substrate molecule (quercetin-4'-glucoside) by homology modelling revealed that hydrophobic interactions dominate the binding of the aglycone moiety. In particular, Val168, Trp345, Phe225, Phe179, Phe334 and Phe433 were identified as likely to be important in determining substrate specificity in hCBG, and site-directed mutagenesis supported a key role for some of these residues.

A comparative infrared spectroscopic study of glycoside hydrolases from extremophilic archaea revealed different molecular mechanisms of adaptation to high temperatures

The identification of the determinants of protein thermal stabilization is often pursued by comparing enzymes from hyperthermophiles with their mesophilic counterparts while direct structural comparisons among proteins and enzymes from hyperthermophiles are rather uncommon. Here, oligomeric beta-glycosidases from the hyperthermophilic archaea Sulfolobus solfataricus (Ss beta-gly), Thermosphaera aggregans (Ta beta-gly), and Pyrococcus furiosus (Pf beta-gly), have been compared. Studies of FTIR spectroscopy and kinetics of thermal inactivation showed that the three enzymes had similar secondary structure composition, but Ss beta-gly and Ta beta-gly (temperatures of melting 98.1 and 98.4 degrees C, respectively) were less stable than Pf beta-gly, which maintained its secondary structure even at 99.5 degrees C. The thermal denaturation of Pf beta-gly, followed in the presence of SDS, suggested that this enzyme is stabilized by hydrophobic interactions. A detailed inspection of the 3D-structures of these enzymes supported the experimental results: Ss beta-gly and Ta beta-gly are stabilized by a combination of ion-pairs networks and intrasubunit S-S bridges while the increased stability of Pf beta-gly resides in a more compact protein core. The different strategies of protein stabilization give experimental support to recent theories on thermophilic adaptation and suggest that different stabilization strategies could have been adopted among archaea.

Crystal structures of Paenibacillus polymyxa beta-glucosidase B complexes reveal the molecular basis of substrate specificity and give new insights into the catalytic machinery of family I glycosidases

Bacteria species involved in degradation of cellulosic substrates produce a variety of enzymes for processing related compounds along the hydrolytic pathway. Paenibacillus polymyxa encodes two homologous beta-glucosidases, BglA and BglB, presenting different quaternary structures and substrate specificities. We previously reported the 3D-structure of BglA, which is highly specific against cellobiose. Here, we present structural analysis of BglB, a monomeric enzyme that acts as an exo-beta-glucosidase hydrolyzing cellobiose and cellodextrins of higher degree of polymerization. The crystal structure of BglB shows that several polar residues narrow the active site pocket and contour additional subsites. The structure of the BglB-cellotetraose complex confirms these subsites, revealing the substrate-binding mode, and shows the oligosaccharide-enzyme recognition pattern in detail. Comparison between BglA and BglB crystal structures suggests that oligomerization in BglA can assist in fine-tuning the specificity of the active centre by modulating the loops surrounding the cavity. We have solved the crystal structure of BglB with bound thiocellobiose, a competitive inhibitor, which together with the BglB-cellotetraose complex delineate the general features of the aglycon site. The detailed characterization of the atomic interactions at the aglycon site show a recognition pattern common to all bacterial beta-glucosidases, and presents some differences with the aglycon site in plant beta-glycosidases essentially by means of a different orientation of the basal Trp. The crystal structures of of BglB with a covalently bound inhibitor (derived from 2-fluoroglucoside) and glucose (produced by hydrolysis of the substrate in the crystal), provide additional pictures of the binding events and the intermediates formed during the reaction. Altogether, this information can assist in the understanding of subtle differences of the enzyme mechanism and substrate recognition within this family of enzymes, and consequently it can help in the development of new enzymes with improved activity or specificity.

Construction of a low-temperature protein expression system using a cold-adapted bacterium, Shewanella sp. strain Ac10, as the host

A recombinant protein expression system working at low temperatures is expected to be useful for the production of thermolabile proteins. We constructed a low-temperature expression system using an Antarctic cold-adapted bacterium, Shewanella sp. strain Ac10, as the host. We evaluated the promoters for proteins abundantly produced at 4 degrees C in this bacterium to express foreign proteins. We used 27 promoters and a broad-host-range vector, pJRD215, to produce beta-lactamase in Shewanella sp. strain Ac10. The maximum yield was obtained when the promoter for putative alkyl hydroperoxide reductase (AhpC) was used and the recombinant cells were grown to late stationary phase. The yield was 91 mg/liter of culture at 4 degrees C and 139 mg/liter of culture at 18 degrees C. We used this system to produce putative peptidases, PepF, LAP, and PepQ, and a putative glucosidase, BglA, from a psychrophilic bacterium, Desulfotalea psychrophila DSM12343. We obtained 48, 7.1, 28, and 5.4 mg/liter of culture of these proteins, respectively, in a soluble fraction. The amounts of PepF and PepQ produced by this system were greater than those produced by the Escherichia coli T7 promoter system.

Crystal structure of intracellular family 1 β-glucosidase BGL1A from the basidiomycetePhanerochaete chrysosporium

The white-rot fungus Phanerochaete chrysosporium has two intracellular beta-glucosidases (BGL1A and BGL1B) belonging to glycoside hydrolase (GH) family 1. BGL1B effectively hydrolyzes cellobiose and cellobionolactone, but BGL1A does not. We have determined the crystal structure of BGL1A in substrate-free and gluconolactone complexed forms. The overall structure and the characteristic of subsite -1 (glycone site) were similar to those of other known GH1 enzymes. The loop regions covering on the (beta/alpha)(8) barrel was significantly deviated, and they form a unique subsite +1 (aglycone site) of BGL1A.

Trehalose biosynthesis in Thermus thermophilus RQ-1: biochemical properties of the trehalose-6-phosphate synthase and trehalose-6-phosphate phosphatase

The genes for trehalose synthesis in Thermus thermophilus RQ-1, namely otsA [trehalose-phosphate synthase (TPS)], otsB [trehalose-phosphate phosphatase (TPP)], and treS [trehalose synthase (maltose converting) (TreS)] genes are structurally linked. The TPS/TPP pathway plays a role in osmoadaptation, since mutants unable to synthesize trehalose via this pathway were less osmotolerant, in trehalose-deprived medium, than the wild-type strain. The otsA and otsB genes have now been individually cloned and overexpressed in Escherichia coli and the corresponding recombinant enzymes purified. The apparent molecular masses of TPS and TPP were 52 and 26 kDa, respectively. The recombinant TPS utilized UDP-glucose, TDP-glucose, ADP-glucose, or GDP-glucose, in this order as glucosyl donors, and glucose-6-phosphate as the glucosyl acceptor to produce trehalose-6-phosphate (T6P). The recombinant TPP catalyzed the dephosphorylation of T6P to trehalose. This enzyme also dephosphorylated G6P, and this activity was enhanced by NDP-glucose. TPS had an optimal activity at about 98 degrees C and pH near 6.0; TPP had a maximal activity near 70 degrees C and at pH 7.0. The enzymes were extremely thermostable: at 100 degrees C, TPS had a half-life of 31 min, and TPP had a half-life of 40 min. The enzymes did not require the presence of divalent cations for activity; however, the presence of Co2+ and Mg2+ stimulates both TPS and TPP. This is the first report of the characterization of TPS and TPP from a thermophilic organism.