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PubMed1979

Purification and properties of human erythrocyte delta-amino-levulinic acid dehydratase (EC 4-2-1-24).

Human delta-aminolevulinic acid dehydratase (ALA-D) was purified 9 000-fold by salt precipitation, ion-exchange chromatography and gel filtration. These methods resulted into an electrophoretically and immunologically pure protein. The optimum pH of the enzyme is 6.6 and its Km with ALA : 4.8 X 10(-4) M. The enzymatic activity was increased by thiol-containing substances, such as dithiothreitol (DTT), which protect the -SH groups of the protein. Zinc, a portion of the enzyme molecule, was partly lost during the purification procedure; its addition enhances the enzymatic activity. Determination of molecular weights and electron microscopy study are in favor of an octameric structure.

Animals↗
PubMed2004

The third case of Doss porphyria (delta-amino-levulinic acid dehydratase deficiency) in Germany.

Delta-aminolevulinic acid dehydratase (ALAD) deficiency porphyria, or Doss porphyria, was first reported in Germany in 1979. Only four bona fide cases of Doss porphyria have been reported to date that were confirmed by immunological and molecular analyses of their ALAD mutations. Here we describe the fifth case of Doss porphyria. A 17-year-old German male suffered from colicky abdominal pain and severe polyneuropathy for 2 years. Urinary delta-aminolevulinic acid (ALA) was increased 32-fold, and coproporphyrin 76-fold compared with the upper limit of their respective normal ranges. Urinary excretion of porphobilinogen (PBG) and uroporphyrin was only slightly increased. Faecal porphyrins were within the normal range. Erythrocyte zinc protoporphyrin concentrations were elevated 5.4-fold. ALAD activity in erythrocytes was decreased to 10% of the normal value, and was not activated by zinc and by dithiothreitol. Blood lead levels were within the normal range, excluding lead poisoning in the proband. Erythrocyte ALAD activity was about one-half of the normal value in both parents, whereas it was normal in the proband's brother. Urinary excretion of ALA, PBG and total porphyrins was within the normal range in both parents and the brother. Molecular genetic studies of the ALAD gene in the proband revealed two base changes, C to A and C to T, both in intron 3 at -11 bp upstream of the exon 3 start site. In addition to the proband, the father carried the (-11)C-to-T, while the mother carried the ALAD gene in the proband's brother. These findings suggest that the observed compound heterozygosity of the ALAD gene may be responsible for Doss porphyria in the proband. The proband was successfully treated with haem arginate infusion. The clinical condition improved, and urinary excretion of ALA and coproporphyrin fell to levels of approximately 50% compared with their pretreatment levels during acute relapses. The haem therapy was continued once weekly for 1 year. At the end of 1 year, urinary ALA and porphyrin levels were significantly lowered, and the proband is now almost free of clinical symptoms.

Abdominal Pain↗
PubMed2006

Qualitative analysis of products formed during the acid catalyzed liquefaction of bagasse in ethylene glycol.

Bagasse was liquefied in ethylene glycol (EG) catalyzed by sulfuric acid at 190 degrees C under atmospheric pressure. The compositions of the crude products obtained were analyzed after separating them into three fractions: a water-soluble fraction, an acetone-soluble fraction and a residue. With infrared, gel permeation chromatography and elemental analyses, the residue mainly included undissolved cellulose and lignin derivatives and the acetone-soluble fraction mainly contained lignin degradation products with high molecular weights. The water-soluble fraction, after further analyzed by GC-MS and HPLC, showed EG, diethylene glycol, EG derivatives, saccharides, alcohols, aldehydes, ketones, phenols, especially some acids such as formic acid, levulinic acid, acetic acid, oxalic acid and 2-hydroxy-butyric acid and their esters. The Higher Heating Value (HHV) of the residue and the acetone-soluble fractions were higher than that of bagasse. The results showed that some useful chemicals and biofuels could be obtained by this process.

Cellulose↗
PubMed2001

The methylcitric acid pathway in Ralstonia eutropha: new genes identified involved in propionate metabolism.

From Ralstonia eutropha HF39 null-allele mutants were created by Tn5 mutagenesis and by homologous recombination which were impaired in growth on propionic acid and levulinic acid. From the molecular, physiological and enzymic analysis of these mutants it was concluded that in this bacterium propionic acid is metabolized via the methylcitric acid pathway. The genes encoding enzymes of this pathway are organized in a cluster in the order prpR, prpB, prpC, acnM, ORF5 and prpD, with prpR transcribed divergently from the other genes. (i) prpC encodes a 2-methylcitric acid synthase (42720 Da) as shown by the measurement of the respective enzyme activity, complementation of a prpC mutant of Salmonella enterica serovar Typhimurium and high sequence similarity. (ii) For the translational product of acnM the function of a 2-methyl-cis-aconitic acid hydratase (94726 Da) is proposed. This protein and also the ORF5 translational product are essential for growth on propionic acid, as revealed by the propionic-acid-negative phenotype of Tn5-insertion mutants, and are required for the conversion of 2-methylcitric acid into 2-methylisocitric acid as shown by the accumulation of the latter, which could be purified as its calcium salt from the supernatants of these mutants. In contrast, inactivation of prpD did not block the ability of the cell to use propionic acid as carbon and energy source, as shown by the propionic acid phenotype of a null-allele mutant. It is therefore unlikely that prpD from R. eutropha encodes a 2-methyl-cis-aconitic acid dehydratase as proposed recently for the homologous prpD gene from S. enterica. (iii) The translational product of prpB encodes 2-methylisocitric acid lyase (32314 Da) as revealed by measurement of the respective enzyme activity and by demonstrating accumulation of methylisocitric acid in the supernatant of a prpB null-allele mutant. (iv) The expression of prpC and probably also of the other enzymes is regulated and is induced during cultivation on propionic acid or levulinic acid. The putative translational product of prpR (70895 Da) exhibited high similarities to PrpR of Escherichia coli and S. enterica, and might represent a transcriptional activator of the sigma-54 family involved in the regulation of the other prp genes. Since the prp locus of R. eutropha was very different from those of E. coli and S. enterica, an extensive comparison of prp loci available from databases and literature was done, revealing two different classes of prp loci.

Alleles↗
PubMed1978

Studies of Delta-Aminolevulinic Acid Dehydrase from Skeletonema costatum, a Marine Plankton Diatom.

The accumulation of delta-aminolevulinic acid and activities of delta-aminolevulinic acid dehydrase were examined in the marine diatom, Skeletonema costatum, grown in the presence of levulinic acid. Levulinic acid concentrations greater than 10 mm affect growth and morphology, and inhibit chlorophyll synthesis. The algae recover from the effects of levulinic acid after 48 hours of exposure. The recovery is characterized by increased cellular cholorphyll content, decreased delta-aminolevulinic acid accumulation, decreased 3-(3,4-dichlorophenyl)-1, 1-dimethylurea-enhanced in vivo fluorescence, and the induction of a levulinic acid-activated delta-aminolevulinic acid dehydrase which does not follow Michaelis-Menten kinetics. The data indicate that levulinic acid blocks may be ineffective in vivo, and that delta-aminolevulinic acid is metabolized to amino and dicarboxylic acids. delta-Aminolevulinic acid dehydrase activities are used to estimate the capacity for chlorophyll synthesis. Results suggest this diatom may be capable of rapid chlorophyll turnover, which would allow the plant to light-shade adapt on the time scales appropriate to vertical mixing rates in the sea.

Journal Article↗
PubMed1996

On the formation of the mixed pyrrole catalysed by porphobilinogen synthase from Rhodobacter spheroides.

This enzyme porphobilinogen synthase (PBGS) catalyses the formation of porphobilinogen (PBG) from two molecules of 5-amino-levulinic acid (ALA). It has been claimed that the PBGS from Rhodobacter spheroides is able to form a mixed pyrrole, from one molecule of 5-aminolevulinic acid and one molecule of levulinic acid. The chemical synthesis of this mixed pyrrole allowed us to show that the compound formed from 5-aminolevulinic acid and levulinic acid with PBGS from R. spheroides has not the proposed structure. The putative enzyme-catalysed formation of the mixed pyrrole has been used as an argument for the postulated mechanism of PBGS. In view of our results, this line of argument has be re-evaluated.

Porphobilinogen Synthase↗
PubMed2003

Production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) with high molar fractions of 3-hydroxyvalerate by a threonine-overproducing mutant of Alcaligenes sp. SH-69.

A threonine overproducing mutant of Alcaligenes sp. SH-69 was isolated and its ability to produce poly(3-hydroxybutyrate-co-3-hydroxyvalerate), poly(3HB-co-3HV), was investigated. The 3HV fraction in poly(3HB-co-3HV) produced from glucose as the sole carbon source exceeded 22 mol%, which is approximately six times higher than that achieved by the wild type under the same culture conditions. Furthermore, the addition of a relatively low concentration (10 mM) of propionic acid, valeric acid or levulinic acid to the glucose medium greatly increased the molar fraction of 3HV in the copolyester, to 38-77 mol%. The results suggest that metabolic engineering of the biosynthetic pathways supplying polyhydroxyalkanoate monomers, such as the threonine biosynthetic pathway, can lead to new poly(3HB-co-3HV)-producing strains.

Alcaligenes↗
PubMed1975

Events surrounding the early development of euglena chloroplasts: v. Control of paramylum degradation.

The degradation of the storage carbohydrate, paramylum, is induced by light in wild-type Euglena gracilis Klebs var. bacillaris Pringsheim and in a mutant, W(3)BUL, which lacks detectable plastid DNA. Treatment of wild type with cycloheximide in the dark produces 60% as much paramylum breakdown as light, whereas treatment with levulinic acid in the dark yields a slightly greater response than light. Both cycloheximide and levulinic acid produce a greater paramylum breakdown in the light than they do in the dark. Treatment of W(3)BUL with levulinic acid in darkness produces a larger paramylum degradation than light, with values similar to wild type in the light. Treatment of W(3)BUL with cycloheximide induces paramylum degradation in darkness, and as with wild type, light is slightly stimulatory in the presence of both cycloheximide or levulinic acid. Streptomycin brings about only a very small amount of paramylum breakdown in the dark and only slightly inhibits breakdown in the light. Thus paramylum breakdown induced by light does not require the synthesis of proteins on cytoplasmic or plastid ribosomes. A model which explains these results postulates the existence of a protein which inhibits paramylum breakdown. When the synthesis of this protein is prevented either by light, cycloheximide, or by levulinic acid acting as a regulatory analog of delta amino levulinic acid, paramylum breakdown takes place. Because levulinic acid is a better inducer than light in W(3)BUL, W(3)BUL may not be able to form as much delta amino levulinic acid in light as wild type. The small amount of induction by streptomycin is viewed as a secondary regulatory effect attributable to interference with plastid protein synthesis which affects regulatory signals from the plastid to the rest of the cell.

Journal Article↗
PubMed2000

Effects of delta-aminolevulinic acid on pigment formation and chlorophyllase activity in French bean leaf.

Chloroplast development and chlorophyll biosynthesis are co-regulated. Treatment by levulinic acid resulted in a linear relation in both chlorophyll and carotenoid contents, during greening of etiolated French bean leaf discs. Chlorophyll biosynthesis appeared to control that of caroteins. In the presence of levulinic acid; at different levels, photosystem II (PS II) activity decreased when expressed on a chlorophyll basis. Chlorophyllase activity was increased progressively by increasing levulinic acid concentration. Thus, levulinic acid could be used to arrest the light-induced chloroplast development at a desired phase of greening and acts as determinator of chloroplast development in green tissues.

Aminolevulinic Acid↗
PubMed1975

Accumulation of delta-Aminolevulinic Acid and Its Relation to Chlorophyll Synthesis and Development of Plastid Structure in Greening Leaves.

Levulinic acid inhibited the greening of etiolated maize (Zea mays) and bean (Phaseolus vulgaris) leaves and caused accumulation of delta-aminolevulinic acid (ALA). ALA accumulation in maize was equivalent to the decrease in chlorophyll, over a wide range of experimental conditions. It was saturated at low light intensities and was not limited by the supply of substrates during the early hours of greening. During 20 hours in light, levulinic acid had little effect on the structural development of thylakoids in bundle sheath chloroplasts but significantly reduced the number and size of thylakoids in grana of mesophyll chloroplasts. Recrystallization of prolamellar bodies and their reformation was inhibited. Mitochondria appeared not to be affected.The accumulation of ALA in bean leaves differed from that in maize in regard to its time course and the effect of levulinic acid concentration and light intensity. The amount of ALA accumulated exceeded that expected from the degree of inhibition of chlorophyll synthesis. Levulinic acid caused abnormalities in the structural development of bean chloroplasts and marked swelling of mitochondria.Chloramphenicol and cycloheximide inhibited ALA accumulation, while inhibitors of RNA synthesis had no effect. The extent of inhibition depended on the time the inhibitor was applied during the greening process. The use of ALA accumulation as a tool for studying the control of chlorophyll synthesis is discussed.

Journal Article↗
PubMed1987

Myeloperoxidase precursors incorporate heme.

Myeloperoxidase of neutrophil granulocytes is synthesized as a larger molecular weight precursor, which is processed to yield mature polypeptides with molecular weights of 62,000 and 12,000. We have investigated the incorporation of heme into myeloperoxidase of the human promyelocytic HL-60 cell line labeled with 5-amino[14C]levulinic acid. Myeloperoxidase was isolated by immunoprecipitation followed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and radiolabeled myeloperoxidase was visualized by fluorography. A 3-h pulse labeling with 5-amino[14C]levulinic acid resulted in labeling of the Mr 90,000 and Mr 82,000 precursor polypeptides. During subsequent chase of the label, conversion to mature radioactive heavy Mr 62,000 subunit was observed but no radioactivity was associated with the mature small Mr 12,000 subunit. Peptide mapping after proteolytic cleavage with V8 proteinase showed that 5-amino[14C]levulinic acid was associated with a single Mr 23,000 polypeptide while multiple radioactive fragments were visible after proteolytic cleavage of myeloperoxidase biosynthetically labeled with [14C]leucine. That 5-amino[14C]levulinic acid was specifically incorporated into heme of myeloperoxidase was also demonstrated by dissociation under reducing conditions which yielded 14C-labeled heme as indicated by reversed phase high pressure liquid chromatography. The ionophore monensin and the base chloroquine, which block processing of myeloperoxidase, did not affect the incorporation of 5-amino[14C]levulinic acid, further supporting the notion that the incorporation of heme is independent of final processing of the polypeptide. Our data establish that heme is incorporated into myeloperoxidase already at the level of the precursor and that processing yields a heme-containing heavy subunit and a heme-free small subunit.

Aminolevulinic Acid↗
PubMed1999

Rhodobacter sphaeroides mutants which accumulate 5-aminolevulinic acid under aerobic and dark conditions.

The photosynthetic bacterium Rhodobacter sphaeroides accumulates 5-aminolevulinic acid (ALA), which is a precursor in tetrapyrrole biosynthesis, under light illumination and upon addition of levulinic acid as an inhibitor of ALA dehydratase. To generate an industrial strain which produces ALA in the absence of light, we sequentially mutated R. sphaeroides CR-286 using N-methyl-N'-nitro-N-nitrosoguanidine (NTG). The mutant strains were screened by cultivating in the absence of light and assayed for ALA by the Ehrlich reaction in a 96-well microtiter plate. The mutant strain CR-386, derived from R. sphaeroides CR-286, was selected as a mutant that exhibited significant ALA accumulation. While CR-286 required light illumination for ALA production, CR-386 was able to accumulate 1.5 mM ALA in the presence of 50 mM glucose, 60 mM glycine, 15 mM levulinic acid and 1.0% (w/v) yeast extract under conditions of agitation in the absence of light. The mutant strain CR-450, derived from strain CR-386, was selected further as a mutant that exhibited significant ALA accumulation but no accumulation of aminoacetone, analogue of ALA. CR-450 accumulated 3.8 mM ALA under the same conditions. In the presence of 50 mM glucose, 60 mM glycine, 5 mM levulinic acid and 1.0% (w/v) yeast extract, the mutant strain CR-520, derived from strain CR-450, and strain CR-606, derived from strain CR-520, accumulated 8.1 mM and 11.2 mM ALA, respectively. In batch fermentation, the strain CR-606 accumulated 20 mM ALA over 18 h after the addition of glycine, levulinic acid, glucose and yeast extract.

Journal Article↗
PubMed2004

[Value of the photodynamic method in the diagnosis of superficial bladder tumors].

Photodynamic diagnosis (PDD) is one of most precise method of neoplasms recognition. The aim of the study was to estimate the value of 5-amino levulinic acid in diagnosis of superficial bladder tumours. Since 1996 to March 2004, 597 cystoscopies were performed with 5-amino levulinic acid in 151 patients with superficial bladder tumours (102 men and 49 women) aged 19-87 years old. 132 pts were treated by PDD after transurethral resection of bladder tumours (TURB). 749 specimens were taken from mucosa during PDD. Before PDD 50 ml of of 5-amino levulinic acid solution was instilled into bladder. As a source of ultraviolet light (UV) D--Light Storz xenon lamp (405 nm) was used. In 16 pts single PDD was performed in 38 double and in 97 PDD was performed three or more times (3 to 7). All pts were observed 12 months before and after PDD. In 102 from 151 pts in white light cystoscopy (WL) no changes in the bladder mucosa were found. In both kind of light (WL and UV) changes were not observed in 44 pts (29.1%). In 58 pts in WL no changes were observed but in UV places of neoplastic changes in the mucosa were found. In these cases the presence of superficial bladder tumours was confirmed. These changes were pathologically confirmed only in UV in 26 pts. Ta (G1 and G2) changes were confirmed in 52 pts (21 in WL and additionally 31 in UV). T1 changes were confirmed in UV in 26 pts but in WL in 25 pts. In 3 pts T2 changes were confirmed in both UV and WL. Cystoscopy in ultraviolet light (photodynamic diagnosis--PDD) with 5 amino levulinic acid gives more precise diagnosis of superficial bladder tumours then the one in standard white light. Cystoscopy performed to diagnose bladder tumours and early recurrence and new focus of tumours recognition without PDD is less effective. Introduction of superficial bladder tumours photodynamic diagnosis into health care system reduced recurrences and improves results of treatment.

Adult↗