Protocatechuic acid production from trans-ferulic acid by Pseudomonas sp. HF-1 mutants defective in protocatechuic acid catabolism

Summary A trans-ferulic acid-utilizing Pseudomonas sp. HF-1 was isolated from soil samples. Mutant HF-1124, capable of growing on trans-ferulic acid but not on protocatechuic acid, was isolated from HF-1 after mutagenesis with nitrosoguanidine. The optimum temperature was 30°C and the optimum pH was 7.0–8.0 for protocatechuic acid production from trans-ferulic acid by mutant HF-1124. Protocatechuic acid production reached 4 g/l from a concentration of 8 g/l trans-ferulic acid. As a result of co-oxidation of methoxy aromatic compounds by strain HF-1124 grown on acetic acid, protocatechuic acid was formed from vanillin and vanillic acid, and vanillic acid and isovanillic acid were formed from veratric acid. By the co-oxidative demethylation of substituted monomethoxybenzene, m- and p-hydroxybenzoic acids were accumulated from m-and p-anisic acid, respectively, while no products were detected from anisole, o-anisic acid, nitroanisole, methylanisole, methoxyphenol and dimethoxybenzene.     

Catabolism of Substituted Benzoic Acids by Streptomyces Species

Four thermotolerant actinomycetes from soil, identified as Streptomyces albulus 321, Streptomyces sioyaensis P5, Streptomyces viridosporus T7A, and Streptomyces sp. V7, were grown at 45°C in media containing either benzoic acid or hydroxyl- and methoxyl-substituted benzoic acids as the principal carbon sources. Benzoic acid was converted to catechol; p-hydroxybenzoic, vanillic, and veratric acids were converted to protocatechuic acid; and m-hydroxybenzoic acid was converted to gentisic acid. Catechol, protocatechuic acid, and gentisic acid were cleaved by catechol 1,2-dioxygenase, protocatechuate 3,4-dioxygenase, and gentisate 1,2-dioxygenase, respectively. Dioxygenases appeared only in induced cultures. m-Hydroxybenzoic, m-anisic, and p-anisic acids were gratuitous inducers of dioxygenases in some strains. One strain converted vanillic acid to guaiacol.     

Degradation of Methoxylated Benzoic Acids by a Nocardia from a Lignin-Rich Environment: Significance to Lignin Degradation and Effect of Chloro Substituents

Strain A81 of Nocardia corallina hydroxylates or demethylates p-anisic acid to p-hydroxybenzoic acid and isovanillic acid. It demethylates veratric acid to a mixture of vanillic and isovanillic acids. These are both demethylated to protocatechuic acid, which undergoes ring cleavage to afford beta-carboxy-cis-cis-muconic acid. The intermediacy of protocatechuic acid in the catabolic pathway of veratric acid was confirmed by blocking ring cleavage with an additional substituent in the ring: 5-chlorovanillic acid was demethylated to 5-chloro-protocatechuic acid, which accumulated. Chloro substituents in the ring of other methoxylated benzoic acids also arrested their normal metabolism by the Nocardia: an ortho-chloro substituent thwarted both demethylation and ring-opening. ortho-Hydroxylation of p-methoxybenzoic acid to isovanillic acid was unaffected by a chlorine ortho to the methoxyl group. Washed whole cells of veratric acid-grown N. corallina A81 produced no detected structural changes in an isolated lignin. The implications of this observation are discussed.     

Transformation of ferulic acid by soil bacteria Nocardia provides various valuable phenolic compounds

Nocardia autotrophica was grown in a medium containing ferulic acid and ¹⁴C-ferulic acid, labelled in various parts of a particle as a main carbon source. After incubation, the products were analyzed by thin layer, high performance liqid and gas chromatography and by IR and NMR spectra methods. The products detected were caffeic acid, catechol, coniferyl alcohol, eugenol, guaiacol, hydrocaffeic acid, isoeugenol, isoferulic acid, isovanillic acid, p-hydroxybenzoic acid, protocatechuic acid and aldehyde, vanillic acid, and vinylguaiacol. A liberation of ¹⁴CO₂ during cultivation was noticed.     

Utilization of complex phenolic compounds by Acinetobacter sp.

Summary Acinetobacter sp. utilized the [ring-¹⁴C]dehydropolymer of coniferyl alcohol (DHP) (sp. act. 1.4 × 10⁴ dpm/mg), ¹⁴C-labelled teakwood lignin (sp. act. 2.5 × 10⁴ dpm/mg), guaiacolglyceryl ether, 2-methoxy-4-formylphenoxyacetic acid, p-benzyloxyphenol, dehydrodivanillyl alcohol, dehydrodiisoeugenol, veratrylglycerol--guaiacyl ether, conidendrin, black liquor lignin and indulin as sole carbon sources. The bacterium produced p-coumaric acid, p-hydroxybenzoic acid, vanillic acid, protocatechuic acid and catechol as intermediates from lignins. Acinetobacter sp. produced catechol 1,2-dioxygenase and protocatechuate 3,4-dioxygenase during the degradation of lignins. Correspondence to: A. Mahadevan     

Microbial transformation of ferulic acid to vanillic acid by <Emphasis Type="Italic">Streptomyces sannanensis</Emphasis> MTCC 6637

Streptomyces sannanensis MTCC 6637 was examined for its potentiality to transform ferulic acid into its corresponding hydroxybenzoate-derivatives. Cultures of S. sannanensis when grown on minimal medium containing ferulic acid as sole carbon source, vanillic acid accumulation was observed in the medium as the major biotransformed product along with transient formation of vanillin. A maximum amount of 400 mg/l vanillic acid accumulation was observed, when cultures were grown on 5 mM ferulic acid at 28°C. This accumulation of vanillic acid was found to be stable in the culture media for a long period of time, thus facilitating its recovery. Purification of vanillic acid was achieved by gel filtration chromatography using Sephadex™ LH-20 matrix. Catabolic route of ferulic acid biotransformation by S. sannanensis has also been demonstrated. The metabolic inhibitor experiment [by supplementation of 3,4 methylenedioxy-cinnamic acid (MDCA), a metabolic inhibitor of phenylpropanoid enzyme 4-hydroxycinnamoyl-CoA ligase (4-CL) along with ferulic acid] suggested that biotransformation of ferulic acid into vanillic acid mainly proceeds via CoA-dependent route. In vitro conversions of ferulic acid to vanillin, vanillic acid and vanillin to vanillic acid were also demonstrated with cell extract of S. sannanensis. Further degradation of vanillic acid to other intermediates such as, protocatechuic acid and guaiacol was not observed, which was also confirmed in vitro with cell extract.     

Degradation of labelled lignins and veratrylglycerol-beta-guaiacyl ether by Acinetobacter sp

Acinetobacter sp. evolved 14CO2 from 14C-(ring)DHP lignin and 14C-teakwood lignin. Veratrylglycerol-beta-guaiacyl ether, a lignin model compound with beta-o-4 linkage was cleaved by Acinetobacter sp. Veratrylglycerol-beta-guaiacyl ether into 2(o-methoxyphenoxy) ethanol and veratrylalcohol 2(o-methoxyphenoxy) ethanol was degraded to guaiacol and then to catechol whereas veratrylalcohol was converted to veratraldehyde, veratric acid, vanillic acid, protocatechuic acid and catechol. Both catechol 1,2-dioxygenase and protocatechuate 3,4-dioxygenase were detected in veratrylglycerol-beta-guaiacyl ether grown cultures.     

Degradation of veratric acid and other lignin-related aromatic compounds by the white-rot fungus Pycnoporus cinnabarinus

Metabolism of veratric acid and other aromatic compounds has been studied in two strains of Pycnoporus cinnabarinus. In non-agitated cultures which contained cellulose as an additional carbon source, veratric acid was demeth(ox)ylated to vanillic acid which accumulated in the medium. Under these conditions, ¹⁴CO₂ evolution from [4-O¹⁴CH₃]-veratric acid preceded that from [3-O¹⁴CH₃]-veratric acid in the case of both strains. ¹⁴CO₂ evolution was markedly accelerated and increased when 100% oxygen was employed instead of air. Oxygen had not so strong effect on the decarboxylation of ¹⁴COOH-labelled vanillic and p-hydroxybenzoic acid but it did increase decarboxylation of ¹⁴COOH-labelled veratric acid, indicating the effect of oxygen on the preceding demeth(ox)ylation. There were indications, for example rapid demethylation of veratric acid in early stages of growth when apparent phenol oxidase (laccase) activity was zero, for an existence of a separate demethylase enzyme. However, the participation of phenol oxidases in demeth(ox)ylation cannot be ruled out. Degradation pattern of vanillic acid was basically similar in P. cinnabarinus compared to Sporotrichum pulverulentum (Phanerochaete chrysosporium). Also the effect of carbon source was similar: cellulose as a carbon source enhanced degradation of vanillic acid through methoxyhydroquinone whereas in glucose medium, vanillic acid was reduced to the respective aldehyde and alcohol.Non-standard abbreviations CBQ cellobiose: quinone oxidoreductase - MHQ methoxyhydroquinone     

Isolation and characterization of an ω3-desaturation-defective mutant of an arachidonic acid-producing fungus,Mortierella alpina 1S-4

A mutant considered to be defective in the conversion of n-6 to n-3 fatty acids (3-desaturation) was derived from a 5-desaturation-defective mutant (Mut44) of Mortierella alpina 1S-4, after treating its spores with N-methyl-N-nitro-N-nitrosoguanidine. This mutant cannot produce 8(Z),11(Z),14(Z),17(Z)-eicosatetraenoic acid or any other n-3 fatty acids, of which about 10% was found in its parental strain upon cultivation at 12°C. The mutant's growth rate was comparable to that of the parental strain when grown at 28°C, but it became much slower when the mutant grew at 12°C, at which the lag phase for Mut44 was about 2 d but 5 d for the mutant.Abbreviations 18:33 9(Z),12(Z),15(Z)-octadecatrienoic acid - 18:43 6(Z),9(Z),12(Z),15(Z)-octadecatetraenoic acid - 20:43 8(Z),11(Z),14(Z),17(Z)-eicosatetraenoic acid - AA arachidonic acid - DHGA dihomo--linolenic acid - EPA 5(Z),8(Z),11(Z),14(Z),17(Z)-eicosapentaenoic acid - GLC gas-liquid chromatography - MNNG N-methyl-N-nitro-N-nitrosoguanidine - PC phosphatidylcholine     

Metabolism of trans-ferulic acid by the white-rot fungus sporotrichum pulverulentum

Ferulic acid metabolism was studied in wild-type Sporotrichum pulverulentum and its phenoloxidase-less mutant, Phe 3. High levels of reduced products which included coniferyl aldehyde, dihydroferulic acid and dihydroconiferyl alcohol were detected in culture filtrates. Small amounts of vanillic acid and methoxyhydroquinone were also found. In addition, products which possessed a methylated p-hydroxyl group were identified by mass spectrometry. The phenoloxidase-less mutant gave essentially the same reduced products as the wildtype. These persisted for longer periods in the culture medium. Three fungi known to produce large amounts of phenoloxidases exhibited a markedly different pattern of ferulic acid depletion.Abbreviations BSTFA N,O-bis-(Trimethylsilyl)trifluoroacetamide - Phe 3 phenoloxidase-less mutant     

Linkage and expression of the Eg locus controlling inclusion of β-glucuronidase into microsomes

In the mouse, one structural gene codes for the amino acid sequence of the -glucuronidase found in both lysosomes and microsomes. The function of a second, independently segregating locus, Eg, is required for the inclusion of -glucuronidase into microsomes. In microsomes, the enzyme, which contains four subunits, is found in a macromolecular complex with up to four additional protein chains; the attachment of these chains is defective in the Eg ⁰ mutant lacking microsomal glucuronidase. The Eg gene has now been linked with Es-1 (1.1±0.3% recombination) on chromosome 8. The -glucuronidase structural gene Gus is on chromosome 5. Thus the gene responsible for processing the polypeptide chain is not genetically linked to the gene directing the synthesisof the enzyme itself.This work was supported in part by the Training Program in Cancer Research, CAO 5016 16, and by U.S. Public Health Service Grant GM 19521.     

Photoactive amino acid derivatives with long alkyl chains

Summary Azobenzene amphiphiles containing-alanine, L-lysine or-homolysine moieties were synthesized and characterised. Stable monomolecular layers at the air/water interface and LB multilayers has been obtained from some of them. One sample of azobenzenes synthesized has been shown to undergo a reversible trans/cis photoisomerization upon light irradiation in both solution and LB multilayer.Abbreviations DCC N,N-dicyclohexyl carbodiimide - HONSu N-hydroxy succinimide - Boc t-butyloxycarbonyl - Bu^t t-butyl - EtOAc ethyl acetate - THF tetrahydrofuran - TEA triethylamine - HPLC high performance liquid chromatography - TLC thin layer chromatography - Ph phenyl - i-PrOH isopropyl alcohol     

Aerobic and Anaerobic Catabolism of Vanillic Acid and Some Other Methoxy-Aromatic Compounds by Pseudomonas sp. Strain PN-1

Vanillic acid (4-hydroxy-3-methoxybenzoic acid) supported the anaerobic (nitrate respiration) but not the aerobic growth of Pseudomonas sp. strain PN-1. Cells grown anaerobically on vanillate oxidized vanillate, p-hydroxybenzoate, and protocatechuic acid (3,4-dihydroxybenzoic acid) with O₂ or nitrate. Veratric acid (3,4-dimethoxybenzoic acid) but not isovanillic acid (3-hydroxy-4-methoxybenzoic acid) induced cells for the oxic and anoxic utilization of vanillate, and protocatechuate was detected as an intermediate of vanillate breakdown under either condition. Aerobic catabolism of protocatechuate proceeded via 4,5-meta cleavage, whereas anaerobically it was probably dehydroxylated to benzoic acid. Formaldehyde was identified as a product of aerobic demethylation, indicating a monooxygenase mechanism, but was not detected during anaerobic demethylation. The aerobic and anaerobic systems had similar but not identical substrate specificities. Both utilized m-anisic acid (3-methoxybenzoic acid) and veratrate but not o- or p-anisate and isovanillate. Syringic acid (4-hydroxy-3,5-dimethoxybenzoic acid), 3-O-methylgallic acid (3-methoxy-4,5-dihydroxybenzoic acid), and 3,5-dimethoxybenzoic acid were attacked under either condition, and formaldehyde was liberated from these substrates in the presence of O₂. The anaerobic demethylating system but not the aerobic enzyme was also active upon guaiacol (2-methoxyphenol), ferulic acid (3-[4-hydroxy-3-methoxyphenyl]-2-propenoic acid), 3,4,5-trimethoxycinnamic acid (3-[3,4,5-trimethoxyphenyl]-2-propenoic acid), and 3,4,5-trimethoxybenzoic acid. The broad specificity of the anaerobic demethylation system suggests that it probably is significant in the degradation of lignoaromatic molecules in anaerobic environments.     

Ilyobacter delafieldii sp. nov., a metabolically restricted anaerobic bacterium fermenting PHB

Enrichments from an estuarine sediment with crotonate as substrate resulted in the isolation of a motile, gram-negative, obligately anaerobic rod with pointed ends, designated strain 10cr1. The organism was asporogenous, did not reduce sulfur, sulfate, thiosulfate, nitrate, oxygen or fumarate, and had a mol %G+C ratio of 29. Strain 10cr1 was able to ferment crotonate, 3-hydroxybutyrate, lactate, pyruvate, and poly--hydroxybutyric acid (PHB). Acetate, propionate, butyrate, CO₂ and H₂ were the fermentation products. When grown on PHB there was accumulation of 3-hydroxybutyrate once growth had ceased, indicating degradation of PHB to the monomer. The 3-hydroxybutyrate formed during growth of the culture was fermented to acetate, butyrate and H₂. Experimental evidence suggested the production of an extracellular PHB depolymerase. The cells were not attached to the PHB granules. This is the first isolation of an anaerobic bacterium capable of degrading exogenous PHB. This strain is described as a new species, Ilyobacter delafieldii sp. nov., and strain 10cr1 (=DSM 5704) is designated as the type (and at present, only) strain.Abbreviations G+C guanine plus cytosine - OD optical density - PHB poly--hydroxybutyric acid - specific growth rate - HPLC high-performance liquid chromatography - YE yeast extract     

A series of mutant strains of Scenedesmus obliquus with abnormal carotenoid compositions

Several mutant strains of Scenedesmus obliquus (Chlorophyta) have been isolated which, when cultured heterotrophically, are pale green or yellow, in contrast to the dark green of the wild type. On the basis of their carotenoid compositions, four groups of pale-green strains have been delineated. These accumulate, respectively, no carotenoid, phytoene, mainly -carotene and mainly -carotene together with some neurosporene and lycopene. All these strains synthesized no chlorophyll b and only small amounts of chlorophyll a. A further group of yellow strains produced the normal Scenedesmus obliquus range of cyclic carotenes and xanthophylls, but no chlorophyll. Most of the pale-green strains were killed by exposure to light, but two strains, PG1 and 1E, which accumulated predominantly -carotene when grown in the dark, survived exposure to the light and developed photosynthetically active chloroplasts containing the normal pigments.The possible biosynthetic implications of the carotenoid composition of these mutant strains, and the relationship between the carotenoid composition and protection of the cells from photooxidative destruction are discussed.Non-Standard Abbreviations TLC thin-layer chromatography     

Xanthoxin levels and metabolism in the wild-type and wilty mutants of tomato

Using ¹³C-labelled internal standards and gas chromatography-mass spectrometry/multiple-ion monitoring the levels of xanthoxin (Xan) and 2-trans-xanthoxin (t-Xan) have been determined in stressed and non-stressed leaves of wildtype tomato (Lycopersicon esculentum Mill cv. Ailsa Craig), and the wilty mutants, notabilis (not), flacca (flc) and sitiens (sit). Levels of Xan were very low in all tissues. Ratios of t-Xan: Xan ranged from 10:1 to <500:1. In the wild-type and flc, t-Xan levels increased following stress. The results from feeding experiments using [¹³C]Xan and t-Xan demonstrated that whilst wild-type and not plants readily converted Xan into abscisic acid (ABA), flc and sit plants converted only a small amount of applied Xan into ABA. In all plants t-Xan was not converted into ABA. These results indicate that the flc and sit mutants are impaired in ABA biosynthesis because they are unable to convert Xan into ABA, whereas the not mutant is blocked at a metabolic step prior to Xan. Another possible ABA precursor, ABA-1,4-trans-diol (ABA-t-diol) was found to occur in wild-type and mutant tissue. All four tissues could convert [²H]ABA-t-diol to ABA. Incubation of stressed leaves in the presence of ¹⁸O₂ provided evidence consistent with Xan and ABA originating via oxidative cleavage of a xanthophyll such as violaxanthin.Abbreviations ABA abscisic acid - ABA-t-diol abscisic acid-1,4-trans-diol - DDC sodium diethyldithiocarbamate - FW fresh weight - GC-MS gas chromatography-mass spectrometry - i.d. internal diameter - MIM multiple-ion monitoring - PA phaseic acid - Xan xanthoxin - flc flacca - not notabilis - sit sitiens     

Appearence and localization of a β-glucosidase hydrolyzing coniferin in spruce (Picea abies) seedlings

-Glucosidase activity for coniferin (coniferyl alcohol -D-glucoside) is not present in spruce (Picea abies L. Karst.) seeds but appears in the young seedlings. Lignification starts at ca. day 9 of germination in the vascular bundles. An antiserum against glucosidase 1 isolated from spruce seedlings (Marcinowski and Grisebach, Eur J. Biochem. 1978) was employed for the localization of the enzyme in cross sections of hypocotyls using immunofluorescent technique. The results indicate that at this stage of development the glucosidase is localized at the inner layer of the secondary cell wall. Glucosidase activity was present in all cells of the investigated hypocotyl tissue.     

Enterotoxin A production in Staphylococcus aureus: inhibition by glucose

In this study, we investigated the relationship between carbohydrate metabolism and repression of staphylococcus enterotoxin A (SEA) in Staphylococcus aureus 196E and a pleiotrophic mutant derived from strain 196E. The mutant, designated at strain 196E-MA, lacked a functional phosphoenolpyruvate phosphotransferase system (PTS). The mutant produced acid, under aerobic conditions, from only glucose and glycerol. The parent strain contained an active PTS, and aerobically produced acid from a large number of carbohydrates. Prior growth in glucose led to repression of SEA synthesis in the parent strain; addition to the casamino acids enterotoxin production medium (CAS) led to more severe repression of toxin synthesis. The repression was not related to pH decreases produced by glucose metabolism. When S. aureus 196E was grown in the absence of glucose, there was inhibition of toxin production as glucose level was increased in CAS. The inhibition was related to pH decrease and was unlike the repression observed with glucose-grown strain 196E. The inhibition of SEA synthesis in mutant strain 196E-MA was approximately the same in cells grown with or without glucose and was pH related. Repression of SEA synthesis similar to that seen with glucose-grown S. aureus 196E could not be demonstrated in the mutant. In addition, glucose-grown S. aureus 196E neither synthesized -galactosidase nor showed respiratory activity with certain tricarboxylic acid (TCA) cycle compounds. Glucose-grown strain 196E-MA, however, did not show supressed respiration of TCA cycle compounds; -galactosidase was not synthesized because the mutant lacked a functional PTS. Cyclic adenosine-3, 5-monophosphate did not reverse the repression by glucose of SEA or -galactosidase synthesis in glucose-grown S. aureus 196E. An active PTS appears to be necessary to demonstrate glucose (catabolite) repression in S. aureus.Abbreviations SEA staphylococcal enterotoxin A - SEB staphylococcal enterotoxin B - SEC staphylococcal enterotoxin C - PTS phosphoenolpyruvate phosphotransferase system - CAS casamino acids salts medium - TCA tricarboxylic acid cycle     

Isolation of Enterobacteria able to degrade simple aromatic compounds from the wastewater from olive oil extraction

Summary Enterobacteria growing on wastewater from olive oil extraction were selected. Among this microflora, strains of Klebsiella oxytoca and Citrobacter diversus able to degrade simple monomeric aromatic compounds were isolated by enrichment culture of the effluent lacking simple sugars. In this preliminary investigation, the phenolic acids tested on solid and liquid media were gentisic, protocatechuic, p-hydroxybenzoic, benzoic, vanillic and ferulic. It was shown that the biodegradation of an aromatic acid is tightly dependent on both the type and the position of the radical substituted on the aromatic ring. Citrobacter was the most efficient strain in metabolizing ferulic acid in liquid medium at a concentration of 1.5 g/l. The substrate biodegradation yield achieved exceeded 86%.