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21.
Polysaccharidases adsorbed on commercial amylodextrins were added to environmentally controlled composts of straw plus poultry manure. After 5 days of composting at 48°C, microbial enzyme activities and numbers of bacteria were higher in the treated compost than in the control. During the next phase at 80°C, between days 5 and 6, more C and N were solubilized in the treated compost. After introducing a microbial inoculum on day 6, and maintaining the substrate at 48°C, colonization by bacteria was faster in the treated compost and consequently, more fibre was degraded. Differences between composts in yields of Agaricus bisporus after 5 weeks of cropping were not significant (P=0.05).The authors are with INRA, Station de Recherches sur les Champignons, BP 81, 33883 Villenave d'Ornon, France 相似文献
22.
Maryvonne Le Coniat Elisabeth Traiffort Martial Ruat Jean-Michel Arrang Roland Berger 《Human genetics》1994,94(2):186-188
We have assigned the human histamine H1-receptor gene to chromosome 3 by Southern blot analysis of a chromosome mapping panel constructed from humanhamster somatic cell hybrids. This assignment was confirmed by in situ hybridization on metaphase chromosomes and involved bands 3p14–p21. 相似文献
23.
Frédérique Tihy Nicolas Vogt Dominique Recan Bernard Malfoy France Leturcq Michelle Coquet Françoise Serville Daniel Fontan Jean-Michel Guillard Jean-Claude Kaplan Bernard Dutrillaux Nicole Lemieux 《Human genetics》1994,93(5):563-567
A girl with severe Becker muscular dystrophy and apparently normal chromosomes had a heterozygous deletion for exons 51, 52, and 53 of the dystrophin gene. This deletion was transmitted by her mother, who was unaffected. To differentiate the normal and the deleted X chromosomes, fluorescence in situ hybridization (FISH) was applied to metaphase chromosomes, using probes for both exons 51 and 52, which are only 388 and 113 base pairs long, respectively. FISH signals were observed in one or both chromatids of one chromosome, but never on both chromosomes, suggesting the lack of hybridization on the deleted X chromosome. Using 5-bromodeoxyuridine incorporation to differentiate the late (inactive) and the early replicating (active) X chromosomes, 77% of the signals were observed on the active X chromosomes in the mother. This percentage was only 18% in the daughter, suggesting that skewed inactivation of the X chromosomes was responsible for the phenotypic differences. 相似文献
24.
Laboratory-scale reactors were used to watch aspects of biodegradation of wheat straw when supplemented with polysaccharidases (Czym) to increase the enzyme production of microorganisms involved during a composting process for mushroom production. Biochemical and biological parameters were tested both under aerobic and O2-limited conditions to assess degradability. These were measurement of released CO2 and NH3, determination of neutral detergent fibre content and cellulase activities from compost extract. The addition of Czym to decomposing straw had three consequences: (i) it supplied and released low quantities of readily available sugars; (ii) it increased the cellulase activities in the substrates; (iii) it increased the number of bacteria under aerobic conditions. The three effects were linked and the small quantity of sugars released by the addition of Czym may have acted as an activator of bacterial activities through an inductive mechanism.
Correspondence to: S. Libmond 相似文献
25.
Alain Gerbi Marcel Debray Jean-Michel Maixent† Claude Chanez Jean-Marie Bourre 《Journal of neurochemistry》1993,60(1):246-252
Abstract: The Na+ sensitivity of whole brain membrane Na+ ,K+ -ATPase isoenzymes was studied using the differential inhibitory effect of ouabain (α1, low affinity for ouabain; α2, high affinity; and α3, very high affinity). At 100 m M Na+ , we found that the proportion of isoforms with low, high, and very high ouabain affinity was 21, 38, and 41%, respectively. Using two ouabain concentrations (10−5 and 10−7 M ), we were able to discriminate Na+ sensitivity of Na+ , K+ -ATPase isoenzymes using nonlinear regression. The ouabain low-affinity isoform, α1, exhibited high Na+ sensitivity [ K a of 3.88 ± 0.25 m M Na+ and a Hill coefficient ( n ) of 1.98 ± 0.13]; the ouabain high-affinity isoform, α2, had two Na+ sensitivities, a high ( K a of 4.98 ± 0.2 m M Na+ and n of 1.34 ± 0.10) and a low ( K a of 28 ± 0.5 m M Na+ and an n of 1.92 ± 0.18) Na+ sensitivity activated above a thresh old (22 ± 0.3 m M Na+ ); and the ouabain very-high-affinity isoform, α3, was resolved by two processes and appears to have two Na+ sensitivities (apparent K a values of 3.5 and 20 m M Na+ ). We show that Na+ dependence in the absence of ouabain is the result of at least of five Na+ reactivities. This molecular functional characteristic of isoenzymes in membranes could explain the diversity of physiological roles attributed to isoenzymes. 相似文献
26.
Rajendra V. Deshpande Jean-Michel Goust Naren L. Banik Ph.D. 《Neurochemical research》1993,18(7):767-773
Calpain, a calcium-activated neutral proteinase, is ubiquitously present in human tissues. To determine if lymphoid cells implicated in pathogenesis of demyelination may harbor calpain in a functionally active form, we determined both Calpain and mCalpain activities in human lymphoid cell lines. DEAE-cellulose and phenylsepharose column chromatography were used to isolate the enzyme from the natural inhibitor, calpastatin. Lymphocytic lines (CCRF-CEM, MOLT-3, MOLT-4, M.R.) showed predominance of Calpain (55–80%) whereas the monocytic line (U-937) showed prodominance of mCalpain (77%). Proportion and subcellular distribution of both isoforms varied among cell lines. Calpains isolated from U-937 cells degraded myelin basic protein. These results indicate that human lymphoid cells harbor functionally active calpain that can degrade myelin components in vitro. The study suggests a degradative role for calpain in demyelinating diseases. 相似文献
27.
Identification of a ClpC ATPase required for stress tolerance and in vivo survival of Listeria monocytogenes 总被引:1,自引:0,他引:1
28.
Bernadette Coddeville Antonin Stratil Jean-Michel Wieruszeski Ronald W. A. Oliver Brian N. Green Genevieve Spik 《Glycoconjugate journal》1995,12(5):645-650
The hemopexin phenotype HpxB1 isolated from sheep serum, yields three major bands when subjected to starch gel and/or polyacrylamide gel electrophoresis which are here designated as subcomponents HpxB1-I, HpxB1-II and HpxB1-III. Electrospray mass spectrometric analysis of samples of the isolated subcomponents prepared by ion exchange chromatography showed that each was composed of three glycoproteins and that the major difference between the subcomponents was due to their constituent glycoproteins possessing different numbers of sialic acid residues. Combined analysis of the ESI-MS data and of the overall carbohydrate compositional data obtained by colorimetric procedures, leads to the composition of the glycan of each glycoprotein, and a combined methylation and 400 MHz H-NMR analysis of the alkaline cleaved glycans identified them as being of only the biantennaryN-acetyllactosamine type. Taking into account the molecular mass, the carbohydrate content and structure it may be concluded that each of the constituent glycoproteins contain fiveN-glycosidically linked glycans.Abbreviations HpxB1
hemopexin phenotype B1
- Man
mannose
- Gal
galactose
- GlcNAc
N-acetylglucosamine
- NeuAc
N-acetylneuraminic acid
- GlcNAc-ol
N-acetylglucosaminitol 相似文献
29.
François-Yves Dupradeau Guillaume Le Flem Jean-Michel Wieruszeski Manuel Dauchez Alain Alix Véronique Larreta-Garde Jean-Pierre Monti 《Letters in Peptide Science》1997,4(4-6):489-495
H-NMR studies of the bovine insulin S-sulfonatedB-chain are reported in H2O/D2O (9/1) and inglycerol-d5 (5 M) using two-dimensional NMRspectroscopy. The first results show that the oxidizedinsulin B-chain secondary structure differs from thatof native insulin by a loss of the -helixbetween the two disulfide bridges and that theglycerol favours the structuring of the peptide. 相似文献
30.
Cuvillier Olivier; Alonso Catherine; Wieruszeski Jean-Michel; Brassart Colette; Strecker Gerard; Bouquelet Stephane; Michalski Jean-Claude 《Glycobiology》1995,5(3):281-289
During a systematic study of carbohydrate material present inhuman meconium, in addition to the previously described mucins,glycolipids and free oligosaccharides, we have now characterizeda significant quantity of free glycoasparagines. These glycoasparagineshave been isolated from human meconium by a combination of ion-exchange,concanavalin A (ConA)-affinity and high-performance liquid (HPLC)chromatographies. Their structures have been established by400 MHz 1H-NMR spectroscopy. These compounds are related toN-acetyllactosaminic type structures and are based on the commoncore These glycoasparagines are probably derived from both proteaseand partial exoglycosidase hydrolysis of fetal gastrointestinalN-glycosyl proteins. Their structures are discussed in the contextof the known catabolic pathways of N-glycans glycoasparagine N-glycosyl protein catabolism meconium NMR 相似文献