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Archives of Microbiology (v.179, #1)

Dissimilation of the C₂ sulfonates by Alasdair M. Cook; Karin Denger (pp. 1-6).

Organosulfonates are widespread in the environment, both as natural products and as xenobiotics; and they generally share the property of chemical stability. A wide range of phenomena has evolved in microorganisms able to utilize the sulfur or the carbon moiety of these compounds; and recent work has centered on bacteria. This Mini-Review centers on bacterial catabolism of the carbon moiety in the C₂-sulfonates and the fate of the sulfonate group. Five of the six compounds examined are subject to catabolism, but information on the molecular nature of transport and regulation is based solely on sequencing data. Two mechanisms of desulfonation have been established. First, there is the specific monooxygenation of ethanesulfonate or ethane-1,2-disulfonate. Second, the oxidative, reductive and fermentative modes of catabolism tend to yield the intermediate sulfoacetaldehyde, which is now known to be desulfonated to acetyl phosphate by a thiamin-diphosphate-dependent acetyltransferase. This enzyme is widespread and at least three subgroups can be recognized, some of them in genomic sequencing projects. These data emphasize the importance of acetyl phosphate in bacterial metabolism. A third mechanism of desulfonation is suggested: the hydrolysis of sulfoacetate.

Keywords: Ethanesulfonate Taurine Isethionate Sulfoacetate Ethanedisulfonate Coenzyme M Sulfoacetaldehyde Sulfoacetaldehyde acetyltransferase Acetyl phosphate

Dissimilation of the C₂ sulfonates by Alasdair M. Cook; Karin Denger (pp. 1-6).

Organosulfonates are widespread in the environment, both as natural products and as xenobiotics; and they generally share the property of chemical stability. A wide range of phenomena has evolved in microorganisms able to utilize the sulfur or the carbon moiety of these compounds; and recent work has centered on bacteria. This Mini-Review centers on bacterial catabolism of the carbon moiety in the C₂-sulfonates and the fate of the sulfonate group. Five of the six compounds examined are subject to catabolism, but information on the molecular nature of transport and regulation is based solely on sequencing data. Two mechanisms of desulfonation have been established. First, there is the specific monooxy-genation of ethanesulfonate or ethane-1,2-disulfonate. Second, the oxidative, reductive and fermentative modes of catabolism tend to yield the intermediate sulfoacetaldehyde, which is now known to be desulfonated to acetyl phosphate by a thiamin-diphosphate-dependent acetyltransferase. This enzyme is widespread and at least three subgroups can be recognized, some of them in genomic sequencing projects. These data emphasize the importance of acetyl phosphate in bacterial metabolism. A third mechanism of desulfonation is suggested: the hydrolysis of sulfoacetate.

Keywords: Ethanesulfonate; Taurine; Isethionate; Sulfoacetate; Ethanedisulfonate; Coenzyme M; Sulfoacetaldehyde; Sulfoacetaldehyde acetyltransferase; Acetyl phosphate

Regulation of formation of the intracellular β-galactosidase activity of Aspergillus nidulans by Erzsébet Fekete; Levente Karaffa; Erzsébet Sándor; Bernhard Seiboth; Sándor Biró; Attila Szentirmai; Christian P. Kubicek (pp. 7-14).

The regulation of formation of the single intracellular β-galactosidase activity of Aspergillus nidulans was investigated. β-Galactosidase was not formed during growth on glucose or glycerol, but was rapidly induced during growth on lactose or D-galactose. L-Arabinose, and – with lower efficacy – D-xylose also induced β-galactosidase activity. Addition of glucose to cultures growing on lactose led to a rapid decrease in β-galactosidase activity. In contrast, in cultures growing on D-galactose, addition of glucose decreased the activity of β-galactosidase only slightly. Glucose inhibited the uptake of lactose, but not of D-galactose, and required the carbon catabolite repressor CreA for this. In addition, CreA also repressed the formation of basal levels of β-galactosidase and partially interfered with the induction of β-galactosidase by D-galactose, L-arabinose, and D-xylose. D-Galactose phosphorylation was not necessary for β-galactosidase induction, since induction by D-galactose occurred in an A. nidulans mutant defective in galactose kinase, and by the non-metabolizable D-galactose analogue fucose in the wild-type strain. Interestingly, a mutant in galactose-1-phosphate uridylyl transferase produced β-galactosidase at a low, constitutive level even on glucose and glycerol and was no longer inducible by D-galactose, whereas it was still inducible by L-arabinose. We conclude that biosynthesis of the intracellular β-galactosidase of A. nidulans is regulated by CreA, partially repressed by galactose-1-phosphate uridylyl transferase, and induced by D-galactose and L-arabinose in independent ways.

Keywords: Aspergillus nidulans β-Galactosidase CreA Lactose Galactose Arabinose

Regulation of formation of the intracellular β-gaiactosidase activity ofAspergillus nidulans by Erzsébet Fekete; Levente Karaffa; Erzsébet Sándor; Bernhard Seiboth; Sándor Biró; Attila Szentirmai; Christian P. Kubicek (pp. 7-14).

The regulation of formation of the single intracellular β-galactosidase activity ofAspergillus nidulans was investigated. β-Galactosidase was not formed during growth on glucose or glycerol, but was rapidly induced during growth on lactose orD-galactose.L-Arabinose, and — with lower efficacy —D-xylose also induced β-galactosidase activity. Addition of glucose to cultures growing on lactose led to a rapid decrease in β-galactosidase activity. In contrast, in cultures growing onD-galactose, addition of glucose decreased the activity of β-galactosidase only slightly. Glucose inhibited the uptake of lactose, but not ofD-galactose, and required the carbon catabolite repressor CreA for this. In addition, CreA also repressed the formation of basal levels of β-galactosidase and partially interfered with the induction of β-galactosidase byD-galactose,L-arabinose, andD-xylose.D-Galactose phosphorylation was not necessary for β-galactosidase induction, since induction byD-galactose occurred in anA. nidulans mutant defective in galactose kinase, and by the non-metabolizableD-galactose analogue fucose in the wild-type strain. Interestingly, a mutant in galactose-1-phosphate uridylyl transferase produced β-galactosidase at a low, constitutive level even on glucose and glycerol and was no longer inducible byD-galactose, whereas it was still inducible byL-arabinose. We conclude that biosynthesis of the intracellular β-galactosidase ofA. nidulans} is regulated by CreA, partially repressed by galactose-1-phosphate uridylyl transferase, and induced byD-galactose andL-arabinose in independent ways.

Keywords: Aspergillus nidulans ; β-Galactosidase; CreA; Lactose; Galactose; Arabinose

New genes involved in chromate resistance in Ralstonia metallidurans strain CH34 by Susanne Juhnke; Nicola Peitzsch; Nicole Hübener; Cornelia Große; Dietrich H. Nies (pp. 15-25).

Chromate resistance in Ralstonia metallidurans CH34 is based on chromate efflux catalyzed by ChrA efflux pumps. The bacterium harbors two chromate resistance determinants, the previously known chr ₁ on plasmid pMOL28 (genes chrI, chrB ₁ , chrA ₁ , chrC, chrE, chrF ₁) and chr ₂ on the chromosome (genes chrB ₂ , chrA ₂ , chrF ₂). Deletion of the genes chrI, chrC, chrA ₂ , chrB ₂ and chrF ₂ influenced chromate resistance and transcription from a chrBp ₁ ::lacZ fusion. Deletion of the plasmid-encoded gene chrB ₁ did not change chromate resistance or chrBp ₁ regulation. Northern hybridization and primer-extension experiments were used to study transcription of the plasmid-encoded chr ₁ determinant. Transcription of chrB ₁ , chrA ₁ and chrC was induced by chromate. The presence of sulfate influenced transcription positively. The chrBp ₁ , chrAp ₁ and chrCp promoters showed some similarity to heat-shock promoters. Transcription of the gene rpoH encoding a putative heat-shock sigma factor was also induced by chromate, but rpoH was not essential for chromate resistance. The ChrC protein was purified as a homotetramer and exerted superoxide dismutase activity. Thus, possible regulators for chromate resistance (ChrI, ChrB₁, ChrB₂, ChrF₁, and ChrF₂) and an additional detoxification system (ChrC) were newly identified as parts of chromate resistance in R. metallidurans.

Keywords: Chromate resistance; Ralstonia metallidurans ; Alcaligenes eutrophus

New genes involved in chromate resistance inRalstonia metallidurans strain CH34 by Susanne Juhnke; Nicola Peitzsch; Nicole Hübener; Cornelia Große; Dietrich H. Nies (pp. 15-25).

Chromate resistance inRalstonia metallidurans CH34 is based on chromate efflux catalyzed by ChrA efflux pumps. The bacterium harbors two chromate resistance determinants, the previously knownchr ₁ on plasmid pMOL28 (geneschrI, chrB ₁,chrA ₁,chrC, chrE, chrF ₁) andchr ₂ on the chromosome (geneschrB ₂,chrA ₂,chrF ₂). Deletion of the geneschrl, chrC, chrA ₂,chrB ₂ andchrF ₂ influenced chromate resistance and transcription from achrBp ₁::lacZ fusion. Deletion of the plasmid-encoded genechrBx did not change chromate resistance orchrBp ₁ regulation. Northern hybridization and primer-extension experiments were used to study transcription of the plasmid-encodedchr ₁ determinant. Transcription ofchrB ₁,chrA ₁ andchrC was induced by chromate. The presence of sulfate influenced transcription positively. ThechrBp ₁,chrAp ₁ andchrCp promoters showed some similarity to heat-shock promoters. Transcription of the generpoH encoding a putative heat-shock sigma factor was also induced by chromate, butrpoH was not essential for chromate resistance. The ChrC protein was purified as a homotetramer and exerted superoxide dismutase activity. Thus, possible regulators for chromate resistance (Chrl, ChrB₁, ChrB₂, ChrF₁, and ChrF₂) and an additional detoxification system (ChrC) were newly identified as parts of chromate resistance inR. metallidurans. Electronic supplementary material to this paper can be obtained by using the Springer LINK server located at http://dx.doi.org/10.1007/s00203-002-0492-5.

Keywords: Chromate resistance; Ralstonia metallidurans ; Alcaligenes eutrophus

Biotin synthase of Bacillus subtilis shows less reactivity than that of Escherichia coli in in vitro reaction systems by Tatsuya Kiyasu; Akira Asakura; Yoshie Nagahashi; Tatsuo Hoshino (pp. 26-32).

The biotin synthases of Bacillus subtilis and Escherichia coli were compared in a physiological reduction system using cell-free extracts and in a artificial reduction system using photo-reduced deazariboflavin. The biotin synthase of B. subtilis was less active than that of E. coli in both reaction systems and showed at least ten-fold less biotin-forming activity than that of E. coli in the artificial reduction system. The physiological reduction system using the biotin synthases and cell-free extracts of B. subtilis and E. coli showed species specificity. The results suggest that the activity of the physiological reduction system of B. subtilis is weaker than that of E. coli. Addition of excess dethiobiotin inhibited biotin formation by growing cells of B. subtilis, but not by E. coli.

Keywords: Biotin synthase Bacillus subtilis Escherichia coli

Biotin synthase ofBacillus subtilis shows less reactivity than that ofEscherichia coil in in vitro reaction systems by Tatsuya Kiyasu; Akira Asakura; Yoshie Nagahashi; Tatsuo Hoshino (pp. 26-32).

The biotin synthases ofBacillus subtilis andEscherichia coli were compared in a physiological reduction system using cell-free extracts and in a artificial reduction system using photo-reduced deazariboflavin. The biotin synthase ofB. subtilis was less active than that ofE. coli in both reaction systems and showed at least tenfold less biotin-forming activity than that ofE. coli in the artificial reduction system. The physiological reduction system using the biotin synthases and cell-free extracts ofB. subtilis andE. coli showed species specificity. The results suggest that the activity of the physiological reduction system ofB. subtilis is weaker than that ofE. coli. Addition of excess dethiobiotin inhibited biotin formation by growing cells ofB. subtilis, but not byE. coli.

Keywords: Biotin synthase; Bacillus subtilis ; Escherichia coli

Enterobacter cloacae rpoS promoter and gene organization by Juana Navarro-Lloréns; Esteban Martínez-García; Antonio Tormo (pp. 33-41).

The upstream region of the Enterobacter cloacae strain CECT960 rpoS gene was sequenced. An IS10R element was found within the nlpD gene, between rpoSp and rpoS. The rpoS promoter, although functional, did not drive transcription of the gene in this strain. However, rpoS transcription depended on this promoter in strains that lacked the insertion sequence in nlpD. rpoSp showed growth-phase-dependent, σ^S-independent regulation. Transcription from rpoSp was strongly inhibited by glucose even though it was cAMP-receptor-protein (CRP)-independent. Its functionality was also independent of both integration host factor (IHF) and the alarmone ppGpp. RpoS-dependent resistance to some environmental stresses showed a quantitative response to RpoS levels under some conditions (alkaline pH and high osmolarity) but not others (acidic pH, high temperature, and UV irradiation).

Keywords: rpoSp Promoter regulation Environmental stress Stationary phase Enterobacter cloacae

Enterobacter cloacae rpoS promoter and gene organization by Juana María Navarro-Lloréns; Esteban Martínez-García; Antonio Tormo (pp. 33-41).

The upstream region of theEnterohacter cloacae strain CECT960rpoS gene was sequenced. AnIS10R element was found within thenlpD gene, betweenrpoSp andrpoS. TherpoS promoter, although functional, did not drive transcription of the gene in this strain. However,rpoS transcription depended on this promoter in strains that lacked the insertion sequence innlpD. rpoSp showed growth-phase-dependent, σ^s-independent regulation. Transcription fromrpoSp was strongly inhibited by glucose even though it was cAMP-receptor-protein (CRP)-independent. Its functionality was also independent of both integration host factor (IHF) and the alarmone ppGpp. RpoS-dependent resistance to some environmental stresses showed a quantitative response to RpoS levels under some conditions (alkaline pH and high osmolarity) but not others (acidic pH, high temperature, and UV irradiation).

Keywords: rpoSp ; Promoter regulation; Environmental stress; Stationary phase; Enterohacter cloacae

Aeropyrum pernix K1, a strictly aerobic and hyperthermophilic archaeon, has two terminal oxidases, cytochrome ba ₃ and cytochrome aa ₃ by Ryuhei Ishikawa; Yoko Ishido; Atsuo Tachikawa; Hiroshi Kawasaki; Hiroshi Matsuzawa; Takayoshi Wakagi (pp. 42-49).

Aeropyrum pernix K1 is a strictly aerobic and hyperthermophilic archaeon that thrives even at 100 °C. The archaeon is quite interesting with respect to the evolution of aerobic electron transport systems and the thermal stability of the respiratory components. An isolated membrane fraction was found to oxidize bovine cytochrome c. The activity was solubilized in the presence of detergents and separated into two fractions by successive chromatography. Two cytochrome oxidases, designated as CO-1 and CO-2, were further purified. CO-1 was a ba ₃-type cytochrome containing at least two subunits. Chemically digested fragments of CO-1 revealed a peptide with a sequence identical to a part of a putative cytochrome oxidase subunit I encoded by the gene ape1623. CO-2, an aa ₃-type cytochrome, was present in lower amounts than CO-1 and was immunologically identified as a product of aoxABC gene (DDBJ accession no. AB020482). Both cytochromes reacted with carbon monoxide. The apparent K _m values of CO-1 and CO-2 for oxygen were 5.5 and 32 µM, respectively, at 25 °C. The terminal oxidases CO-1 and CO-2 phylogenetically correspond to the SoxB and SoxM branches, respectively, of the heme-copper oxidase tree.

Keywords: Heme-copper oxidase Cytochrome oxidase Cytochrome ba3 Cytochrome aa3 respiratory chain Aeropyrum pernix Hyperthermophile Archaea

Aempyrum pernix K1, a strictly aerobic and hyperthermophilic archaeon, has two terminal oxidases, cytochromeBa ₃ and cytochromeaa ₃ by Ryuhei Ishikawa; Yoko Ishido; Atsuo Tachikawa; Hiroshi Kawasaki; Hiroshi Matsuzawa; Takayoshi Wakagi (pp. 42-49).

Aeropyrum pernix K1 is a strictly aerobic and hyperthermophiiic archaeon that thrives even at 100 °C. The archaeon is quite interesting with respect to the evolution of aerobic electron transport systems and the thermal stability of the respiratory components. An isolated membrane fraction was found to oxidize bovine cytochromec. The activity was solubilized in the presence of detergents and separated into two fractions by successive chromatography. Two cytochrome oxidases, designated as CO-1 and CO-2, were further purified. CO-1 was aba ₃-type cytochrome containing at least two subunits. Chemically digested fragments of CO-1 revealed a peptide with a sequence identical to a part of a putative cytochrome oxidase subunit I encoded by the geneape 1623. CO-2, anaa ₃-type cytochrome, was present in lower amounts than CO-1 and was immunologically identified as a product ofaoxABC gene (DDBJ accession no. AB020482). Both cytochromes reacted with carbon monoxide. The apparentK _m values of CO-1 and CO-2 for oxygen were 5.5 and 32 µM, respectively, at 25 °C. The terminal oxidases CO-1 and CO-2 phylogenetically correspond to the SoxB and SoxM branches, respectively, of the heme-copper oxidase tree.

Keywords: Heme-copper oxidase; Cytochrome oxidase; Cytochromeba ₃ ; Cytochromeaa ₃ respiratory chain; Aeropyrum pernix ; Hyperthermophile; Archaea

Transport of molybdate in the cyanobacterium Anabaena variabilis ATCC 29413 by Teresa Thiel; Brenda Pratte; Marta Zahalak (pp. 50-56).

Heterocyst-forming filamentous cyanobacteria, such as Anabaena variabilis ATCC 29413, require molybdenum as a component of two essential cofactors for the enzymes nitrate reductase and nitrogenase. A. variabilis efficiently transported ⁹⁹Mo (molybdate) at concentrations less than 10^–9 M. Competition experiments with other oxyanions suggested that the molybdate-transport system of A. variabilis also transported tungstate but not vanadate or sulfate. Although tungstate was probably transported, tungsten did not function in place of molybdenum in the Mo-nitrogenase. Transport of ⁹⁹Mo required prior starvation of the cells for molybdate, suggesting that the Mo-transport system was repressed by molybdate. Starvation, which required several generations of growth for depletion of molybdate, was enhanced by growth under conditions that required synthesis of nitrate reductase or nitrogenase. These data provide evidence for a molybdate storage system in A. variabilis. NtcA, a regulatory protein that is essential for synthesis of nitrate reductase and nitrogenase, was not required for transport of molybdate. The closely related strain Anabaena sp. PCC 7120 transported ⁹⁹Mo in a very similar way to A. variabilis.

Keywords: Cyanobacteria Anabaena Molybdate Molybdenum Metal transport

Transport of molybdate in the cyanobacteriumAnabaena variabilis ATCC 29413 by Teresa Thiel; Brenda Pratte; Marta Zahalak (pp. 50-56).

Heterocyst-forming filamentous cyanobacteria, such asAnahaena variabilis ATCC 29413, require molybdenum as a component of two essential cofactors for the enzymes nitrate reductase and nitrogenase.A. variabilis efficiently transported⁹⁹Mo (molybdate) at concentrations less than 10⁻⁹ M. Competition experiments with other oxyanions suggested that the molybdate-transport system ofA. variabilis also transported tungstate but not vanadate or sulfate. Although tungstate was probably transported, tungsten did not function in place of molybdenum in the Mo-nitrogenase. Transport of⁹⁹Mo required prior starvation of the cells for molybdate, suggesting that the Mo-transport system was repressed by molybdate. Starvation, which required several generations of growth for depletion of molybdate, was enhanced by growth under conditions that required synthesis of nitrate reductase or nitrogenase. These data provide evidence for a molybdate storage system inA. variabilis. NtcA, a regulatory protein that is essential for synthesis of nitrate reductase and nitrogenase, was not required for transport of molybdate. The closely related strainAnabaena sp. PCC 7120 transported⁹⁹Mo in a very similar way toA. variabilis.

Keywords: Cyanobacteria; Anabaena ; Molybdate; Molybdenum; Metal transport

The Vibrio fischeri sapABCDF locus is required for normal growth, both in culture and in symbiosis by Claudia Lupp; Robert E. Hancock; Edward G. Ruby (pp. 57-65).

Inactivation of the sapABCDF genes results in a loss of virulence in several bacterial pathogens of animals and plants. The role of this locus in the growth physiology of Vibrio fischeri, and in the symbiotic colonization of the squid Euprymna scolopes was investigated. In rich medium, a V. fischeri sapA insertion mutant grew at only 85% the rate of its wild-type parent. While a similar effect has been attributed to a potassium-transport defect in sap mutants of enteric bacteria, the V. fischeri mutant grew more slowly regardless of the potassium concentration of the medium. Similarly, the growth-rate defect was independent of the source of either carbon, nitrogen, or phosphorous, indicating that the V. fischeri sap genes do not encode functions required for the transport of a specific form of any of these nutrients. Finally, while a delay in colonizing the nascent light organ of the squid could be accounted for by the lower growth rate of the mutant, a small but statistically significant reduction in its final population size in the host, but not in medium, suggests that the sap genes play another role in the symbiosis. All of these phenotypic defects could be genetically complemented in trans by the sapABCDF genes, but not by the sapA gene alone, indicating that the insertion in sapA is polar to the four downstream genes in the locus. Thus, while the sap locus is important to the normal growth of V. fischeri, it plays different physiological roles in growth and tissue colonization than it does in enteric pathogens.

Keywords: Vibrio fischeri Symbiosis Growth sapABCDF

TheVibrio fischeri sapABCDF locus is required for normal growth, both in culture and in symbiosis by Claudia Lupp; Robert E. W. Hancock; Edward G. Ruby (pp. 57-65).

Inactivation of thesapABCDF genes results in a loss of virulence in several bacterial pathogens of animals and plants. The role of this locus in the growth physiology ofVibrio fischeri, and in the symbiotic colonization of the squidEuprymna scolopes was investigated. In rich medium, aV. fischeri sapA insertion mutant grew at only 85% the rate of its wild-type parent. While a similar effect has been attributed to a potassium-transport defect insap mutants of enteric bacteria, theV. fischeri mutant grew more slowly regardless of the potassium concentration of the medium. Similarly, the growth-rate defect was independent of the source of either carbon, nitrogen, or phosphorous, indicating that theV. fischeri sap genes do not encode functions required for the transport of a specific form of any of these nutrients. Finally, while a delay in colonizing the nascent light organ of the squid could be accounted for by the lower growth rate of the mutant, a small but statistically significant reduction in its final population size in the host, but not in medium, suggests that thesap genes play another role in the symbiosis. All of these phenotypic defects could be genetically complementedin trans by thesapABCDF genes, but not by thesapA gene alone, indicating that the insertion insapA is polar to the four downstream genes in the locus. Thus, while thesap locus is important to the normal growth ofV. fischeri, it plays different physiological roles in growth and tissue colonization than it does in enteric pathogens.

Keywords: Vibrio fischeri ; Symbiosis; Growth; sapABCDF

A possible role of poly-3-hydroxybutyric acid in antibiotic production in Streptomyces by Shivani Verma; Yukti Bhatia; Sabeel Valappil; Ipsita Roy (pp. 66-69).

The occurrence of poly-3-hydroxybutyric acid (PHB) in 12 different strains of the genus Streptomyces was investigated. Gas chromatographic estimation indicated that all the strains produced PHB and the range of maximum PHB accumulation was between 1.5 and 11.8% dry cell weight. PHB was isolated from Streptomyces coelicolor A3(2) M145 and characterized using Fourier transform-infrared (FT-IR) spectroscopy. The correlation between PHB utilization and antibiotic production in S. coelicolor A3(2) M145, was studied; results indicated a possible role of PHB as a carbon reserve material used for antibiotic production.

Keywords: Polyhydroxyalkanoates Poly-3-hydroxybutyric acid Streptomyces Gas chromatography FT-IR spectroscopy 3-Hydroxybutyric acid methyl ester Actinorhodin γ-Actinorhodin Undecylprodigiosin

A possible role of poly-3-hydroxybuiyric acid in antibiotic production inStreptomyces by Shivani Verma; Yukti Bhatia; Sabeel Padinhara Valappil; Ipsita Roy (pp. 66-69).

The occurrence of poly-3-hydroxybutyric acid (PHB) in 12 different strains of the genusStreptomyces was investigated. Gas chromatographic estimation indicated that all the strains produced PHB and the range of maximum PHB accumulation was between 1.5 and 11.8% dry cell weight. PHB was isolated fromStreptomyces coelicolor A3(2) M145 and characterized using Fourier transform-infrared (FT-ER) spectroscopy. The correlation between PHB utilization and antibiotic production inS. coelicolor A3(2) Ml45, was studied; results indicated a possible role of PHB as a carbon reserve material used for antibiotic production.

Keywords: Polyhydroxyalkanoates; Poly-3-hydroxybutyric acid; Streptomyces ; Gas chromatography; FT-IR spectroscopy; 3-Hydroxybutyric acid methyl ester; Actinorhodin; γ-Actinorhodin; Undecylprodigiosin

Properties of a laccase produced by Phanerochaete flavido-alba induced by vanillin by Teresa de la Rubia; Esteban Ruiz; Juana Pérez; José Martínez (pp. 70-73).

Phanerochaete flavido-alba is able to remove simple and polymeric phenols from the recalcitrant wastes of the olive oil industry, in a process in which a laccase is involved. This report describes the characterization of a laccase produced by P. flavido-alba and induced by vanillin. Although the amino acid composition of the purified enzyme is typical for laccases, other molecular characteristics show that it is quite different from fungal laccases. The purified laccase oxidized preferably o- and p-biphenols.

Keywords: Laccase Phanerochaete Phanerochaete flavido-alba

Properties of a laccase produced byPhanerochaete flavido-alba induced by vanillin by Teresa de la Rubia; Esteban Ruiz; Juana Pérez; José Martínez (pp. 70-73).

Phanerochaete flavido-alba is able to remove simple and polymeric phenols from the recalcitrant wastes of the olive oil industry, in a process in which a laccase is involved. This report describes the characterization of a laccase produced byP. flavido-alba and induced by vanillin. Although the amino acid composition of the purified enzyme is typical for laccases, other molecular characteristics show that it is quite different from fungal laccases. The purified laccase oxidized preferablyo- andp-biphenols.

Keywords: Laccase; Phanerochaete ; Phanerochaete flavido-alba

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Archives of Microbiology (v.179, #1)