共查询到20条相似文献,搜索用时 15 毫秒
1.
Guy P. Mannaerts Paul P. Van Veldhoven M. Casteels 《Cell biochemistry and biophysics》2000,32(1-3):73-87
Peroxisomal β-oxidation is involved in the degradation of long chain and very long chain fatty acyl-(coenzyme A)CoAs, long
chain dicarboxylyl-CoAs, the CoA esters of eicosanoids, 2-methyl-branched fatty acyl-CoAs (e.g. pristanoyl-CoA), and the CoA
esters of the bile acid intermediates di- and trihydroxycoprostanic acids (side chain of cholesterol).
In the rat, straight chain acyl-CoAs (including the CoA esters of dicarboxylic fatty acids and eicosanoids) are β-oxidized
via palmitoyl-CoA oxidase, multifunctional protein-1 (which displays 2-enoyl-CoA hydratase and L-3-hydroxyacyl-CoA, dehydrogenase
activities) and peroxisomal thiolase. 2-Methyl-branched acyl-CoAs are degraded via pristanoyl-CoA oxidase, multifunctional
protein-2 (MFP-2) (which displays 2-enoyl-CoA hydratase and D-3-hydroxyacyl-CoA dehydrogenase activities) and sterol carrier
protein-X (SCPX; displaying 2-methyl-3-oxoacyl-CoA thiolase activity). The side chain of the bile acid intermediates is shortened
via one cycle of β-oxidation catalyzed by trihydroxycoprostanoyl-CoA oxidase, MFP-2 and SCPX. In the human, straight chain
acyl-CoAs are oxidized via palmitoyl-CoA oxidase, multifunctional protein-1, and peroxisomal thiolase, as is the case in the
rat. The CoA esters of 2-methyl-branched acyl-CoAs and the bile acid intermediates, which also possess a 2-methyl substitution
in their side chain, are shortened, via branched chain acyl-CoA oxidase (which is the human homolog of trihydroxycoprostanoyl-CoA
oxidase), multifunctional protein-2, and SCPX. The rat and the human enzymes have been purified, cloned, and kinetically and
stereochemically characterized.
3-Methyl-branched fatty acids such as phytanic acid are not directly β-oxidizable because of the position of the methyl-branch.
They are first shortened by one carbon atom through the a-oxidation process to a 2-methyl-branched fatty acid (pristanic acid
in the case of phytanic acid), which is then degraded via peroxisomal β-oxidation. In the human and the rat, α-oxidation is
catalyzed by an acyl-CoA synthetase (producing a 3-methylacyl-CoA), a 3-methylacyl-CoA 2-hydroxylase (resulting in a 2-hydroxy-3-methylacyl-CoA),
and a 2-hydroxy-3-methylacyl-CoA lyase that cleaves the 2-hydroxy-3-methylacyl-CoA into a 2-methyl-branched fatty aldehyde
and formyl-CoA. The fatty aldehyde is dehydrogenated by an aldehyde dehydrogenase to a 2-methyl-branched fatty acid while
formyl-CoA is hydrolyzed to formate, which is then converted to CO2. The activation, hydroxylation and cleavage reactions and the hydrolysis of formyl-CoA are performed by peroxisomal enzymes;
the aldehyde dehydrogenation remains to be localized whereas the conversion of formate to CO2 occurs mainly in the cytosol. 相似文献
2.
Sabria Defnoun Maurice Ambrosio Jean-Louis Garcia Alfred Traoré Marc Labat 《Current microbiology》2003,46(1):0047-0052
A syntrophic consortium was enriched in a basal medium containing cinnamate as the carbon and energy source. It was found
to consist of three morphologically distinct microbes, viz., a short, rod-shaped, non-motile bacterium with distinctly pointed
ends, Papillibacter cinnamivorans; a rod-shaped, motile bacterium with rounded ends, Syntrophus sp.; and a methanoarchaeon, Methanobacterium sp. This methanogen was then replaced by a collection strain of Methanobacterium formicicum. A syntrophic interdependency of the three partners of the consortium was observed during growth on cinnamate. In the presence
of bromoethanesulfonic acid (BESA), cinnamate was transformed to benzoate, whereas under methanogenic conditions without BESA,
cinnamate was first transformed to benzoate via β-oxidation and subsequently completely degraded into acetate, CH4, and CO2. Papillibacter cinnamivorans was responsible for benzoate production from cinnamate, whereas a syntrophic association between Syntrophus sp. and the methanogen degraded benzoate to acetate, CH4, and CO2. A new anaerobic degradation pathway of cinnamate into benzoate via β-oxidation by a pure culture of P. cinnamivorans is proposed.
Received: 27 December 2001 / Accepted: 28 March 2002 相似文献
3.
Gulevich AY Skorokhodova AY Sukhozhenko AV Shakulov RS Debabov VG 《Biotechnology letters》2012,34(3):463-469
The basic reactions of the clostridial 1-butanol biosynthesis pathway can be regarded to be the inverted reactions of the
fatty acid β-oxidation pathway. A pathway for the biosynthesis of fuels and chemicals was recently engineered by combining
enzymes from both aerobic and anaerobic fatty acid β-oxidation as well as enzymes from other metabolic pathways. In the current
study, we demonstrate the inversion of the entire aerobic fatty acid β-oxidation cycle for 1-butanol biosynthesis. The constructed
markerless and plasmidless Escherichia coli strain BOX-3 (MG1655 lacI
Q
attB-P
trc-ideal-4-SDφ10-adhE(Glu568Lys) attB-P
trc-ideal-4-SDφ10-atoB attB-P
trc-ideal-4-SDφ10-fadB attB-P
trc-ideal-4-SDφ10-fadE) synthesises 0.3–1 mg 1-butanol/l in the presence of the specific inducer. No 1-butanol production was detected in the absence
of the inducer. 相似文献
4.
Secondaryn-alkyl sulfates (and secondary alkanols) prove to be degraded aerobically by aPseudomonas species (Ps. B-2) to carbon dioxide, water and sulfate. The proposed mechanism for the biodegradation proceeds via the alcohol → ketone
→ hydroxyketone → dione → aldehyde + acid. Consequently, two fatty acids are formed which are subsequently degraded by β-oxidation.
This pathway requires the presence of molecular oxygen for the hydroxylation of the ketone. Attempts to isolate bacteria growing
on secondary alcohols anaerobically were unsuccessful. 相似文献
5.
Indole-3-butyric acid (IBA) is an endogenous auxin that acts in Arabidopsis primarily via its conversion to the principal auxin indole-3-acetic acid (IAA). Genetic and biochemical evidence indicates
that this conversion is similar to peroxisomal fatty acid β-oxidation, but the specific enzymes catalyzing IBA β-oxidation
have not been identified. We identified an IBA-response mutant (ibr3) with decreased responses to the inhibitory effects of IBA on root elongation or the stimulatory effects of IBA on lateral
root formation. However, ibr3 mutants respond normally to other forms of auxin, including IAA. The mutant seedlings germinate and develop normally, even
in the absence of sucrose, suggesting that fatty acid β-oxidation is unaffected. Additionally, double mutants between ibr3 and acx3, which is defective in an acyl-CoA oxidase acting in fatty acid β-oxidation, have enhanced IBA resistance, consistent with
a distinct role for IBR3. Positional cloning revealed that IBR3 encodes a putative acyl-CoA dehydrogenase with a consensus peroxisomal targeting signal. Based on the singular defect of this
mutant in responding to IBA, we propose that IBR3 may act directly in the oxidation of IBA to IAA.
Electronic supplementary material The online version of this article (doi: ) contains supplementary material, which is available to authorized users. 相似文献
6.
Y. Pagot A. Le Clainche J.-M. Nicaud Y. Wache J.-M. Belin 《Applied microbiology and biotechnology》1998,49(3):295-300
γ-Decalactone is a peachy aroma compound resulting from the peroxisomal β-oxidation of ricinoleic acid by yeasts. The expression
levels of acyl-CoA oxidase (gene deletion) and 3-ketoacyl-CoA thiolase activities (gene amplification on replicative plasmids)
were modified in the yeast Yarrowia lipolytica. The effects of these modifications on β-oxidation were measured. Overexpression of thiolase activity did not have any effect
on the overall β-oxidation activity. The disruption of one of the acyl-CoA oxidase genes resulted in an enhanced activity.
The enhancement led to an increase of overall β-oxidation activity but reduced the γ-decalactone production rates. This seemed
to indicate a non-rate-limiting role for β-oxidation in the biotransformation of ricinoleic acid to γ-decalactone by the yeast
Yarrowia lipolytica. All strains produced and then consumed γ-decalactone. We checked the ability of the different strains to consume γ-decalactone
in a medium containing the lactone as sole carbon source. The consumption of the strain overexpressing acyl-CoA oxidase activity
was higher than that of the wild-type strain. We␣concluded that peroxisomal β-oxidation is certainly involved in γ-decalactone
catabolism by the yeast Y.␣lipolytica. The observed production rates probably depend on an equilibrium between production and consumption of the lactone.
Received: 13 June 1997 / Received revision: 2 October 1997 / Accepted: 14 October 1997 相似文献
7.
Haloferax sp. D1227, isolated from soil contaminated with highly saline oil brine, is the first halophilic archaeon to demonstrate
the utilization of aromatic compounds (i.e., benzoic acid, cinnamic acid, and 3-phenylpropionic acid) as sole carbon and energy
sources for growth. The degradation of 3-phenylpropionic acid in this strain was studied to examine the strategies utilized
by Archaea to metabolize aromatic compounds. Based on our findings of (1) the extracellular accumulation of cinnamic acid,
benzoic acid, 3-hydroxybenzoic acid, and gentisic acid in cultures of Haloferax D1227 grown on 3-phenylpropionic acid, (2) the presence of an 3-phenylpropionylCoA dehydrogenase, (3) the ATP, CoA, and NAD-dependent
conversion of cinnamic acid to benzoylCoA, and (4) the presence of gentisate 1,2-dioxygenase, we propose that Haloferax D1227 metabolizes 3-phenylpropionic acid by initial 2-carbon shortening of the side chain to benzoylCoA via a mechanism similar
to fatty acid β-oxidation, fol-lowed by aromatic degradation using a gentisate pathway. The upper aliphatic pathway from 3-phenylpropionic
acid to benzoic acid is regulated separately from the lower gentisate pathway.
Received: January 7, 1998 / Accepted: July 22, 1998 相似文献
8.
Susana Valenciano J. Ramón De Lucas A. Pedregosa Inmaculada F. Monistrol F. Laborda 《Archives of microbiology》1996,166(5):336-341
Aspergillus nidulans is able to grow on oleic acid as sole carbon source. Characterization of the oleate-induced β-oxidation pathway showed the
presence of the two enzyme activities involved in the first step of this catabolic system: acyl-CoA oxidase and acyl-CoA dehydrogenase.
After isopicnic centrifugation in a linear sucrose gradient, microbodies (peroxisomes) housing the β-oxidation enzymes, isocitrate
lyase and catalase were clearly resolved from the mitochondrial fraction, which contained fumarase. Growth on oleic acid was
associated with the development of many microbodies that were scattered throughout the cytoplasm of the cells. These microbodies
(peroxisomes) were round to elongated, made up 6% of the cytoplasmic volume, and were characterized by the presence of catalase.
The β-oxidation pathway was also induced in acetate-grown cells, although at lower levels; these cells lacked acyl-CoA oxidase
activity. Nevertheless, growth on acetate did not cause a massive proliferation of microbodies in A. nidulans.
Received: 8 March 1996 / Accepted: 5 August 1996 相似文献
9.
Stable-isotope-labelled (2H6,18O) 3-hydroxy-3-phenylpropanoic acid, a putative intermediate in the biosynthesis of benzoic acid (BA) and salicylic acid (SA)
from cinnamic acid, has been synthesized and administered to cucumber (Cucumis sativus L.) and Nicotiana attenuata (Torrey). Analysis of the products by gas chromatography-mass spectrometry revealed incorporation of labelling into BA and
SA, but not into benzaldehyde. In a separate experiment, 3-hydroxy- 3-phenylpropanoic acid was found to be a metabolite of
phenylalanine, itself the primary metabolic precursor of BA and SA. These data suggest that cinnamic acid chain shortening
is probably achieved by β-oxidation, and that the proposed “non-oxidative” pathway of side-chain degradation does not function
in the biosynthesis of BA and SA, in cucumber and N. attenuata.
Received: 10 February 2000 / Accepted: 18 April 2000 相似文献
10.
During the glyoxysomal β-oxidation of long-chain acyl-CoAs, short-chain intermediates accumulate transiently (Kleiter and
Gerhardt 1998, Planta 206: 125–130). The studies reported here address the underlying factors. The studies concentrated upon
the aspects of (i) chain length specificity and (ii) metabolic regulation of the glyoxysomal β-oxidation of sunflower (Helianthus annuus L.) cotyledons. (i) Concentration-rate curves of the β-oxidation of acyl-CoAs of various chain lengths showed that the β-oxidation
activity towards long-chain acyl-CoAs was higher than that towards short-chain acyl-CoAs at substrate concentrations <20 μM.
At substrate concentrations >20 μM, long-chain acyl-CoAs were β-oxidized more slowly than short-chain acyl-CoAs because the
β-oxidation of long-chain acyl-CoAs is subject to substrate inhibition which had already started at 5–10 μM substrate concentration
and results from an inhibition of the multifunctional protein (MFP) of the β-oxidation reaction sequence. However, low concentrations
of free long-chain acyl-CoAs are rather likely to exist within the glyoxysomes due to the acyl-CoA-binding capacity of proteins.
Consequently, the β-oxidation rate towards a parent long-chain acyl-CoA will prevail over that towards the short-chain intermediates.
(ii) Low concentrations (≤5 μM) of a long-chain acyl-CoA exerted an inhibitory effect on the β-oxidation rate of butyryl-CoA.
Reversibility of the inhibition was observed as well as metabolization of the inhibiting long-chain acyl-CoA. Regarding the
activities of the individual β-oxidation enzymes towards their C4 substrates in the presence of a long-chain acyl-CoA, the MFP activity exhibited strong inhibition. This inhibition appears
not to be due to the detergent-like physical properties of long-chain acyl-CoAs. The results of the studies, which are consistent
with the observation that short-chain intermediates accumulate transiently during complete degradation of a long-chain acyl-CoA,
suggest that the substrate concentration-dependent chain-length specificity of the β-oxidation and a metabolic regulation
at the level of MFP are factors determining this transient accumulation.
Received: 2 February 1999 / Accepted: 14 April 1999 相似文献
11.
Haddouche R Poirier Y Delessert S Sabirova J Pagot Y Neuvéglise C Nicaud JM 《Applied microbiology and biotechnology》2011,91(5):1327-1340
Recombinant strains of the oleaginous yeast Yarrowia lipolytica expressing the PHA synthase gene (PhaC) from Pseudomonas aeruginosa in the peroxisome were found able to produce polyhydroxyalkanoates (PHA). PHA production yield, but not the monomer composition,
was dependent on POX genotype (POX genes encoding acyl-CoA oxidases) (Haddouche et al. FEMS Yeast Res 10:917–927, 2010). In this study of variants of the Y. lipolytica β-oxidation multifunctional enzyme, with deletions or inactivations of the R-3-hydroxyacyl-CoA dehydrogenase domain, we were
able to produce hetero-polymers (functional MFE enzyme) or homo-polymers (with no 3-hydroxyacyl-CoA dehydrogenase activity) of PHA consisting principally of 3-hydroxyacid
monomers (>80%) of the same length as the external fatty acid used for growth. The redirection of fatty acid flux towards
β-oxidation, by deletion of the neutral lipid synthesis pathway (mutant strain Q4 devoid of the acyltransferases encoded by
the LRO1, DGA1, DGA2 and ARE1 genes), in combination with variant expressing only the enoyl-CoA hydratase 2 domain, led to a significant increase in PHA
levels, to 7.3% of cell dry weight. Finally, the presence of shorter monomers (up to 20% of the monomers) in a mutant strain
lacking the peroxisomal 3-hydroxyacyl-CoA dehydrogenase domain provided evidence for the occurrence of partial mitochondrial
β-oxidation in Y. lipolytica. 相似文献
12.
Aspergillus nidulans can use a variety of fatty acids as sole carbon and energy sources via its peroxisomal and mitochondrial β-oxidation pathways.
Prior to channelling the fatty acids into β-oxidation, they need to be activated to their acyl-CoA derivates. Analysis of
the genome sequence identified a number of possible fatty acyl-CoA synthetases (FatA, FatB, FatC, FatD, FaaA and FaaB). FaaB
was found to be the major long-chain synthetase for fatty acid degradation. FaaB was shown to localise to the peroxisomes,
and the corresponding gene was induced in the presence of short and long chain fatty acids. Deletion of the faaB gene leads to a reduced/abolished growth on a variety of fatty acids. However, at least one additional fatty acyl-CoA synthetase
with a preference for short chain fatty acids and a potential mitochondrial candidate (AN4659.3) has been identified via genome
analysis. 相似文献
13.
14.
Hu CA Donald SP Yu J Lin WW Liu Z Steel G Obie C Valle D Phang JM 《Molecular and cellular biochemistry》2007,299(1-2):85-92
The neuropathogenesis of influenza-associated encephalopathy in children and Reye's syndrome remains unclear. A surveillance
effort conducted during 2000-2003 in South-West Japan reveals that almost all fatal and handicapped influenza-associated encephalopathy
patients exhibit a disorder of mitochondrial β-oxidation with elevated serum acylcarnitine ratios (C16:0+C18:1)/C2. Here we show invasion by a non-neurotropic epidemic influenza A H3N2 virus in cerebral capillaries with progressive brain
edema after intranasal infection of mice having impaired mitochondrial β-oxidation congenitally or posteriorly in the newborn/
suckling periods. Mice genetically lacking of carnitine transporter OCTN2, resulting in carnitine deficiency and impaired
β-oxidation, exhibited significant higher virus-genome numbers in the brain, accumulation of virus antigen exclusively in
the cerebral capillaries and increased brain vascular permeability compared to in wild type mice. Mini-plasmin, which proteolytically
potentiates influenza virus multiplication in vivo and destroys the blood-brain barrier, accumulated with virus antigen in the brain capillaries of OCTN2-deficient mice but
only a little in wild-type mice. These results suggest that the impaired mitochondrial β-oxidation changes the susceptibility
to a non-neurotropic influenza A virus as to multiplication in the brain capillaries and to cause brain edema. These pathological
findings in the brain of mice having impaired mitochondrial β-oxidation after influenza virus infection may have implications
for human influenza-associated encephalopathy. 相似文献
15.
M. L. Hector M. F. Murphy-Waldorf T. B. Giertych M. J. Hickey A. A. Haggard 《World journal of microbiology & biotechnology》1993,9(5):562-565
Eighteen non-sibling mutants of Pseudomonas aeruginosa PAO were isolated that were deficient in the utilization of the -methyl branched acid citronellic acid but not in the utilization of the unbranched n-octanoic acid (Cau mutants). These mutants are also deficient in the utilization of citronellol and citronellal. R68.45 plasmid-mediated transfer of chromosomal material has been used to map one of the mutations at about 52 min on the PAO chromosome and to show linkage of some, but not all, of the other mutations to this region. This system is of interest for bioremediation in oil spill areas since -methyl branches block normal -oxidation and cause recalcitrance of organic molecules present in petroleum products. 相似文献
16.
Potential of Rhodococcus strains for biotechnological vanillin production from ferulic acid and eugenol 总被引:1,自引:0,他引:1
Plaggenborg R Overhage J Loos A Archer JA Lessard P Sinskey AJ Steinbüchel A Priefert H 《Applied microbiology and biotechnology》2006,72(4):745-755
The potential of two Rhodococcus strains for biotechnological vanillin production from ferulic acid and eugenol was investigated. Genome sequence data of Rhodococcus sp. I24 suggested a coenzyme A-dependent, non-β-oxidative pathway for ferulic acid bioconversion, which involves feruloyl–CoA synthetase (Fcs), enoyl–CoA hydratase/aldolase (Ech), and vanillin dehydrogenase (Vdh). This pathway was proven for Rhodococcus opacus PD630 by physiological characterization of knockout mutants. However, expression and functional characterization of corresponding structural genes from I24 suggested that degradation of ferulic acid in this strain proceeds via a β-oxidative pathway. The vanillin precursor eugenol facilitated growth of I24 but not of PD630. Coniferyl aldehyde was an intermediate of eugenol degradation by I24. Since the genome sequence of I24 is devoid of eugenol hydroxylase homologous genes (ehyAB), eugenol bioconversion is most probably initiated by a new step in this bacterium. To establish eugenol bioconversion in PD630, the vanillyl alcohol oxidase gene (vaoA) from Penicillium simplicissimum CBS 170.90 was expressed in PD630 together with coniferyl alcohol dehydrogenase (calA) and coniferyl aldehyde dehydrogenase (calB) genes from Pseudomonas sp. HR199. The recombinant strain converted eugenol to ferulic acid. The obtained data suggest that genetically engineered strains of I24 and PD630 are suitable candidates for vanillin production from eugenol. 相似文献
17.
A. J. Willetts 《Antonie van Leeuwenhoek》1973,39(1):585-597
A study was made of the biodegradation of 1-phenylundecane-p-sulphonate and 1-phenyldodecane-p-sulphonate byCladosporium resinae (CMI 88968) which was capable of growth on a number of such alkylbenzene sulphonate homologues as the sole source of carbon
and sulphur. The results from both whole-cell and cell-free systems indicated that the alkyl, aryl and sulphonate moieties
of detergent homologues were metabolised by the fungus. The alkyl side-chain, after a presumed initial oxidation of the terminal
methyl group, was subsequently oxidised by a β-oxidation pathway. Three enzymes of the β-oxidation pathway, i.e. acyl-CoA
synthetase, acyl-CoA dehydrogenase and β-hydroxyacyl-CoA dehydrogenase were identified in detergent-grown cell-free extracts
of the fungus. The sulphonate moiety was released as sulphate by a desulphonating enzyme. The combined results of continuous
sampling programmes monitored by both TLC and sulphate appearance in the growth medium indicated that desulphonation of the
aromatic moiety was an early event in the overall biodegradation of synthetic detergent homologues. The presence of 1-phenylvalerate,
1-phenylpropionate, benzoate,p-hydroxybenzoate and 3,4-dihydroxybenzoate in cells after growth on 1-phenylundecane-p-sulphonate was indicated by GLC analysis. Cells grown on 1-phenyldodecane-p-sulphonate were shown to contain 1-phenylhexanoate, 1-phenylbutyrate, phenylacetate,p-hydroxyphenylacetate and 3,4-dihydroxyphenylacetate. The aromatic nuclei remaining after alkyl side-chain biodegradation
were further metabolised by an oxidation sequence involving an “ortho-cleavage” pathway. An overall metabolic pathway for
the biodegradation of alkylbenzene sulphonates byCladosporium resinae is proposed. 相似文献
18.
Le Thi Nhi-Cong Annett Mikolasch Hans-Peter Klenk Frieder Schauer 《International biodeterioration & biodegradation》2009,63(2):201-207
Pristane, a highly branched hydrocarbon that also contains iso-branched termini, was used as a substrate for several alkane-metabolizing bacteria. Rhodococcus ruber and Mycobacterium neoaurum were able to utilize pristane for growth effectively. The intermediates produced by these bacteria during incubation with pristane were analyzed by gas chromatography (GC) and gas chromatography/mass spectra (GC/MS). The products revealed as products of 4-methyl pentanoic acid; methyl butanedioic acid; 2-methyl pentadioic acid; methyl propanedioic acid; 4-methyl heptanedioic acid; and 2,6,10,14-tetramethyl-pentadecan-3-one were detected in M. neoaurum cultures. In R. ruber, methyl butanedioic acid; 2-methyl pentadioic acid; 4,8-dimethylnonanoic acid, 4-methyl heptanedioic acid; 2,6,10-trimethylundecanoic acid; 3,7-dimethyl decanedioic acid; and 2,6,10,14-tetramethyl-pentadecan-3-one were detected. The occurrence of these intermediates showed that pristane could be catabolized not only via mono- but also by a di-terminal oxidation pathway. Furthermore, the presence of 2,6,10,14-tetramethyl-pentadecan-3-one; 3,7-dimethyldecandioate; and 2-methylbutandioate established a third pathway initiated by sub-terminal oxidation at the third carbon atom of pristane. Novel intermediates detected suggest simultaneous sub-terminal and di-terminal oxidation pathways. 相似文献
19.
trans-Stilbene degradation was examined by the reaction using resting cells of microorganisms isolated through the enrichment culture
using trans-stilbene. The strain SL3, showing the highest trans-stilbene-degrading activity, was identified as Arthrobacter sp. One of the reaction products was identified to be cis,cis-muconic acid. Arthrobacter sp. SL3 cells also transformed benzaldehyde, benzoic acid and catechol into cis,cis-muconic acid, suggesting that one benzene ring of trans-stilbene was converted into cis,cis-muconic acid via benzaldehyde formed by its Cα=Cβ bond cleavage. 相似文献
20.
The basidiomycete Phanerochaete chrysosporium produces several β-1,3-glucanases when grown on laminarin, a β-1,3/1,6-glucan, as the sole carbon source. To characterize
one of the major unknown β-1, 3-glucanases with a molecular mass of 83 kDa, identification, cloning, and heterologous over-expression
were carried out using the total genomic information of P. chrysosporium. The cDNA encoding this enzyme included an ORF of 2337 bp and the deduced amino acid sequence contains a predicted signal
peptide of 26 amino acids and the mature protein of 752 amino acids. The amino acid sequence showed a significant similarity
with glycoside hydrolase family 55 enzymes from filamentous fungi and was named Lam55A. Since the recombinant Lam55A expressed
in the methylotrophic yeast Pichia pastoris degraded branched β-1,3/1,6-glucan as well as linear β-1,3-glucan, the kinetic features of the enzyme were compared with
those of other β-1,3-glucanases. 相似文献