ABSTRACT
An endo-beta-mannanase (EC 3.2.1.78) from Streptomyces ipomoea CECT 3341 was purified and applied to the biobleaching of pine kraft pulps. The maximum level of endo-beta-mannanase activity (0.6 units ml(-1)) was achieved after 4 days of growth in a medium containing locust bean gum and yeast extract. Zymograms revealed mannanase bands (Man) with high and low electrophoretic mobility on the second and seventh days of incubation (Man1, Man3) and three bands of high, medium and low mobility from the third to sixth days of growth (Man1, Man2, Man3). Although these exhibited different molecular masses, their amino-terminal sequences were identical. The action of proteases detected in the culture supernatant could be responsible for such events, suggesting that only one endo-beta-mannanase is produced by S. ipomoea. The purified Man3 exhibited a molecular mass of 40 kDa, an isoelectric point of 4.0 and an optimal temperature and pH reaction of 55 degrees C and 7.5, respectively. It was strongly inhibited by Ag+, Hg2+, Al3+ and Fe3+, and was strongly activated by Mn2+. The ability of the purified endo-beta-mannanase to improve the bleachability of pine kraft pulp, when applied with alkaline extraction, was demonstrated by an increase in the pulp brightness (1.7%, using the International Standards Organisation's test) and an absence of variations in the viscosity values. A relationship between the increase in pulp brightness and the presence of manganese in the pulps could be established.
Subject(s)
Industry/methods , Mannosidases/metabolism , Paper , Streptomyces/enzymology , Wood , Amino Acid Sequence , Mannosidases/chemistry , Mannosidases/genetics , Molecular Sequence Data , Streptomyces/growth & developmentABSTRACT
Alkali-lignin samples obtained from an untreated paper mill effluent and from the effluent decolourised by the strains Streptomyces avermitilis CECT 3339 and Streptomyces scabies UAH 51 were analysed by gas chromatography-mass spectrometry (GC-MS) after cupric oxide degradation. The analysis of the depolymerisation products of the alkali-lignin from the decolourised effluents showed a strain specific modification of the aromatic moiety of the alkali-lignin. Moreover, both strains were able to breakdown the aryl-alkyl ether linkages between the cinnamic acids and the lignin. Finally, GC-MS analysis showed that both strains oxidised the alkali-lignin regardless of its initial degree of oxidation.
Subject(s)
Copper/chemistry , Gas Chromatography-Mass Spectrometry/methods , Lignin/analysis , Streptomyces/metabolism , Alkalies , Color , Lignin/metabolismABSTRACT
Seven wastewater sludges of different origins and types were used as an alternate culture medium for producing Bacillus thuringiensis variety kurstaki HD-1. The sludge samples were used under three different preparations: without pre-treatment, with acid treatment (hydrolysed sludge) and the supernatant obtained after centrifugation of the hydrolysed sludge. The sludge composition varied widely with origin and the type of sludge. Growth and sporulation were evaluated by the total viable cell count and spore count of the preparations. Growth, sporulation and endotoxin production were affected by the sludge origin. Hydrolysed sludge gave the highest viable cell and spore counts while the liquid phase (supernatant) gave the lowest. Non-hydrolysed primary sludge from Valcartier was unable to sustain bacterial growth because of its low pH. Bioassays were conducted against larvae of spruce budworm to evaluate entomotoxic potential of the preparations obtained. In general, sludge hydrolysis increased the entomotoxicity yields. Similar entomotoxicity was observed in Black Lake secondary sludge (4100 IU/microL) as that obtained in the reference soya medium (3800 IU/microL). The use of the sludge supernatant (liquid phase) was not recommended due to the low entomotoxic potential obtained.
Subject(s)
Bacillus thuringiensis/growth & development , Conservation of Natural Resources , Culture Media , Sewage/microbiology , Biological Assay , Hydrogen-Ion Concentration , Pest Control , Population Dynamics , SporesABSTRACT
The genetic variation of orosomucoid (ORM1 and ORM2) in three south-western European populations (Galicia, Spanish Basque Country and northern Portugal) was investigated using hybrid isoelectric focusing. Three common ORM1 alleles were observed in these populations, the frequencies of ORM1 *S observed in Galicia and northern Portugal being the highest found among populations of European origin. Rare variants were observed for both the ORM1 and ORM2 loci.
Subject(s)
Gene Frequency , Orosomucoid/genetics , Genetic Variation , Humans , Isoelectric Focusing , Portugal , SpainABSTRACT
alpha1-Antitrypsin (Pi), transferrin (Tf) and orosomucoid (ORM) were determined in bloodstain extracts by isoelectric focusing (IEF) with carrier ampholytes (CA) and also with a mixture of immobilines (HIEF). HIEF yields superior results from proteins typing in bloodstain extracts, since phenotypes are better distinguished and the bands are straighter and sharper. Also the sensitivity of HIEF is similar to IEF with CA.
Subject(s)
Blood Stains , Isoelectric Focusing/methods , Orosomucoid/analysis , Transferrin/analysis , alpha 1-Antitrypsin/analysis , Humans , Hydrogen-Ion ConcentrationSubject(s)
Orosomucoid/analysis , Polymorphism, Genetic , Humans , Isoelectric Focusing/methods , PhenotypeABSTRACT
Optimal programs for the separation of polymorphic proteins and enzymes in miniaturized polyacrylamide gels using an automated system (PhastSystem) are described. The potential advantages and disadvantages of the method and its application to forensic science laboratories are discussed.
Subject(s)
Enzymes/analysis , Isoelectric Focusing/methods , Proteins/analysis , Acrylic Resins , Automation , Forensic Medicine/methods , Humans , Miniaturization , Phenotype , Polymorphism, GeneticABSTRACT
Orosomucoid (ORM) polymorphism was investigated by different methods including isoelectric focusing in acid pH ranges followed by silver staining, print immunofixation of desialyzed ORM, fixation using a lectin from the sea-weed Codium tomentosum, isoelectric focusing followed by immunofixation in miniaturized gels and isoelectric focusing in immobilized pH gradients. Population genetics studies were carried out in Galicia (NW Spain) and two new ORM variants were found.
Subject(s)
Isoelectric Focusing/methods , Orosomucoid/genetics , Alleles , Ampholyte Mixtures , Gels , Humans , Immunochemistry , Lectins , Neuraminidase/pharmacology , Phenotype , Silver , Spain , Staining and Labeling , Terminology as TopicABSTRACT
The correlation between ORM phenotypes in untreated serum and ORM phenotypes after isoelectric focusing of neuraminidase-treated serum is demonstrated. ORM subtypes were determined using isoelectric focusing in immobilized pH gradients. Population genetic studies of ORM polymorphism in the Galician population were also carried out.
Subject(s)
Asialoglycoproteins , Gene Frequency , Orosomucoid/analogs & derivatives , Orosomucoid/genetics , Humans , Isoelectric Focusing , Orosomucoid/analysis , Phenotype , Polymorphism, Genetic , SpainABSTRACT
Galactose-1-phosphate uridyl transferase (GALT), esterase D (EsD), and plasminogen (PLG) phenotypes were determined by isoelectric focusing in thin-layer polyacrylamide gels (PAGIF) in a random sample from Galicia. Haptoglobins (Hp) were determined by conventional electrophoresis. The following gene frequencies were observed: for GALT: GALTN: 0.930; GALTD1: 0.044; GALTD2: 0.025; for EsD: EsD1: 0.874; EsD2: 0.104; EsD3: 0.021; for PLG: PLG1: 0.800; PLG2: 0.199; for Hp: Hp1: 0.426; Hp2: 0.573. Population data results of all electrophoretic markers typed until now in Galician population are also included.
