共查询到20条相似文献,搜索用时 15 毫秒
1.
Chaoning Liang Yanfen Xue Marco Fioroni Francisco Rodríguez-Ropero Cheng Zhou Ulrich Schwaneberg Yanhe Ma 《Applied microbiology and biotechnology》2011,89(2):315-326
A β-1,4-endoglucanase (Cel5A) was cloned from the genomic DNA of saccharolytic thermophilic eubacterium Thermoanaerobacter tengcongensis MB4 and functionally expressed in Escherichia coli. Substrate specificity analysis revealed that Cel5A cleaves specifically the β-1,4-glycosidic linkage in cellulose with high
activity (294 U mg−1; carboxymethyl cellulose sodium (CMC)). On CMC, kinetics of Cel5A was determined (K
m 1.39 ± 0.12 g l−1; k
cat/K
m 1.41 ± 0.13 g−1 s−1). Cel5A displays an activity optimum between 75 and 80 °C. Residues Glu187 and Glu289 were identified as key catalytic amino
acids by sequence alignment. Interestingly, derived from a non-halophilic bacterium, Cel5A exhibits high residual activities
in molar concentration of NaCl (3 M, 49.3%) and KCl (4 M, 48.6%). In 1 M NaCl, 82% of Cel5A activity is retained after 24
h incubation. Molecular Dynamics studies performed at 0 and 3 M NaCl, correlate the Cel5A stability to the formation of R-COO−···Na+ ···−OOC-R salt bridges within the Cel5A tertiary structure, while activity possibly relates to the number of Na+ ions trapped into the negatively charged active site, involving a competition mechanism between substrate and Na+. Additionally, Cel5A is remarkably resistant in ionic liquids 1-butyl-3-methyllimidazolium chloride (1 M, 54.4%) and 1-allyl-3-methylimidazolium
chloride (1 M, 65.1%) which are promising solvents for cellulose degradation and making Cel5A an attractive candidate for
industrial applications. 相似文献
2.
A recombinant putative glycoside hydrolase from Caldicellulosiruptor saccharolyticus was purified with a specific activity of 12 U mg−1 by heat treatment and His-Trap affinity chromatography, and identified as a single 56 kDa band upon SDS-PAGE. The native
enzyme is a dimer with a molecular mass of 112 kDa as determined by gel filtration. The enzyme exhibited its highest activity
when debranched arabinan (1,5-α-l-arabinan) was used as the substrate, demonstrating that the enzyme was an endo-1,5-α-l-arabinanase. The K
m, k
cat, and k
cat/K
m values were 18 mg ml−1, 50 s−1, and a 2.8 mg ml−1 s−1, respectively. Maximum enzyme activity was at pH 6.5 and 75°C. The half-lives of the enzyme at 65, 70 and 75°C were 2440,
254 and 93 h, respectively, indicating that it is the most thermostable of the known endo-1,5-α-l-arabinanases. 相似文献
3.
Chavan SP Lokhande VH Nitnaware KM Nikam TD 《Applied microbiology and biotechnology》2011,89(6):1701-1707
The present study examined the effects of plant growth hormones, incubation period, biotic (Trametes versicolor, Mucor sp., Penicillium notatum, Rhizopus stolonifer, and Fusarium oxysporum) and abiotic (NaCl, MgSO4, FeSO4, ZnSO4, and FeCl3) elicitors on cell growth and α-tocopherol and pigment (red and yellow) productions in Carthamus tinctorius cell cultures. The cell growth and α-tocopherol and pigment contents improved significantly on Murashige and Skoog (MS) liquid
medium containing 50.0 μM α-naphthalene acetic acid (NAA) and 2.5 μM 6-Benzyladenine (BA) at 28 days of incubation period.
Incorporation of T. versicolor (50 mg l−1) significantly enhanced the production of α-tocopherol (12.7-fold) and red pigment (4.24-fold). Similarly, supplementation
of 30 mg l−1
T. versicolor (7.54-fold) and 70 mg l−1
Mucor sp. (7.40-fold) significantly increased the production of yellow pigment. Among abiotic elicitors, NaCl (50–70 mg l−1) and MgSO4 (10–30 mg l−1) significantly improved production of α-tocopherol (1.24-fold) and red pigment (20-fold), whereas yellow pigment content
increased considerably by all the abiotic elicitor treatments. Taken together, the present study reports improved productions
of α-tocopherol and the pigment as a stress response of safflower cell cultures exposed to these elicitors. 相似文献
4.
Kim HT Ko HJ Kim N Kim D Lee D Choi IG Woo HC Kim MD Kim KH 《Biotechnology letters》2012,34(6):1087-1092
A gene, alg7D, from Saccharophagus degradans, coding for a putative alginate lyase belonging to the family of polysaccharide lyase-7, was overexpressed in Escherichia coli. The properties of the recombinant Alg7D were characterized. The enzyme endolytically depolymerized alginate by β-elimination
into oligo-alginates with degrees of polymerization of 2–5. Its activity was maximal at 50°C and pH 7 and was slightly increased
in the presence of Na+. The K
M
, V
max
, k
cat
, and k
cat
/K
M
values were: 3 mg ml−1, 6.2 U mg−1, 1.9 × 10−2 s−1, and 6.3 × 10−3 mg−1 ml s−1, respectively. 相似文献
5.
Hee-Jung Moon Manish Tiwari Marimuthu Jeya Jung-Kul Lee 《Applied microbiology and biotechnology》2010,87(1):205-214
Ribitol dehydrogenase (RDH) catalyzes the conversion of ribitol to d-ribulose. A novel RDH gene was cloned from Zymomonas mobilis subsp. mobilis ZM4 and overexpressed in Escherichia coli BL21(DE3). DNA sequence analysis revealed an open reading frame of 795 bp, capable of encoding a polypeptide of 266 amino
acid residues with a calculated molecular mass of 28,426 Da. The gene was overexpressed in E. coli BL21(DE3) and the protein was purified as an active soluble form using glutathione S-transferase affinity chromatography. The molecular mass of the purified enzyme was estimated to be ∼28 kDa by sodium dodecyl
sulfate-polyacrylamide gel and ∼58 KDa with gel filtration chromatography, suggesting that the enzyme is a homodimer. The
enzyme had an optimal pH and temperature of 9.5 and 65°C, respectively. Unlike previously characterized RDHs, Z. mobilis RDH (ZmRDH) showed an unusual dual coenzyme specificity, with a k
cat of 4.83 s−1 for NADH (k
cat/K
m = 27.3 s−1 mM−1) and k
cat of 2.79 s−1 for NADPH (k
cat/K
m = 10.8 s−1 mM−1). Homology modeling and docking studies of NAD+ and NADP+ into the active site of ZmRDH shed light on the dual coenzyme specificity of ZmRDH. 相似文献
6.
Identification of carotenoids with high antioxidant capacity produced by extremophile microorganisms
F Mandelli VS Miranda E Rodrigues AZ Mercadante 《World journal of microbiology & biotechnology》2012,28(4):1781-1790
In this study, the carotenoids produced by the extremophile microorganisms Halococcus morrhuae, Halobacterium salinarium and Thermus filiformis were separated and identified by high-performance liquid chromatography connected to a diode array detector and a tandem
mass spectrometer. The in vitro scavenging capacity of the carotenoid extracts against radical and non-radical species was
evaluated. In halophilic microorganisms, the following carotenoids were identified: bacterioruberin, bisanhydrobacterioruberin,
trisanhydrobacterioruberin and their derivatives. In the thermophilic bacterium, the carotenoids all-trans-zeaxanthin, zeaxanthin monoglucoside, thermozeaxanthins and thermobiszeaxanthins were identified. The antioxidant capacities
of the carotenoid extracts of H. morrhuae (trolox equivalent antioxidant capacity = 5.07 and IC50 = 0.85 μg mL−1) and H. salinarium (trolox equivalent antioxidant capacity = 5.28 and IC50 = 0.84 μg mL−1) were similar and higher than those of the bacterium T. filiformis (trolox equivalent antioxidant capacity = 2.87 and IC50 = 2.41 μg mL−1). This difference is related to the presence of acyclic carotenoids with both large numbers of conjugated double bounds and
of hydroxyl groups in the major carotenoid of the halophilic microorganisms. 相似文献
7.
Archaeal microorganisms that grow optimally at Na+ concentrations of 1.7 M, or the equivalent of 10% (w/v) NaCl, and greater are considered to be extreme halophiles. This review
encompasses extremely halophilic archaea and their growth characteristics with respect to the correlation between the extent
of alkaline pH and elevated temperature optima and the extent of salt tolerance. The focus is on poly-extremophiles, i.e.,
taxa growing optimally at a Na+ concentration at or above 1.7 M (approximately 10% w/v NaCl); alkaline pH, at or above 8.5; and elevated temperature optima,
at or above 50°C. So far, only a very few extreme halophiles that are able to grow optimally under alkaline conditions as
well as at elevated temperatures have been isolated. The distribution of extremely halophilic archaea growing optimally at
3.4 M Na+ (approximately 20% w/v NaCl) is bifurcated with respect to pH optima, either they are neutrophilic, with a pHopt of approximately 7, or strongly alkaliphilic, with pHopt at or above 8.5. Amongst these extreme halophiles which have elevated pH optima, only four taxa have an optimum temperature
above 50°C: Haloarcula quadrata (52°C), Haloferax elongans (53°C), Haloferax mediterranei (51°C) and Natronolimnobius
‘aegyptiacus’ (55°C). 相似文献
8.
Ki-Hyun Park O-Mi Lee Ho-Il Jung Jin-Ha Jeong Young-Dong Jeon Dae-Youn Hwang Chung-Yeol Lee Hong-Joo Son 《Applied microbiology and biotechnology》2010,86(3):947-955
We isolated and characterized novel insoluble phosphate (P)-solubilizing bacteria tolerant to environmental factors like high
salt, low and high pHs, and low temperature. A bacterium M6 was isolated from a ginseng rhizospheric soil and confirmed to
belong to Burkholderia vietnamiensis by BIOLOG system and 16S rRNA gene analysis. The optimal cultural conditions for the solubilization of P were 2.5% (w/v) glucose, 0.015% (w/v) urea, and 0.4% (w/v) MgCl2·6H2O along with initial pH 7.0 at 35°C. High-performance liquid chromatography analysis showed that B. vietnamiensis M6 produced gluconic and 2-ketogluconic acids. During the culture, the pH was reduced with increase in gluconic acid concentration
and was inversely correlated with P solubilization. Insoluble P solubilization in the optimal medium was about 902 mg l−1, which was approximately 1.6-fold higher than the yield in NBRIP medium (580 mg l−1). B. vietnamiensis M6 showed resistance against different environmental stresses like 10–45°C, 1–5% (w/v) salt, and 2–11 pH range. The maximal concentration of soluble P produced by B. vietnamiensis M6 from Ca3(PO4)2, CaHPO4, and hydroxyapatite was 1,039, 2,132, and 1,754 mg l−1, respectively. However, the strain M6 produced soluble P with 20 mg l−1 from FePO4 after 2 days and 100 mg l−1 from AlPO4 after 6 days, respectively. Our results indicate that B. vietnamiensis M6 could be a potential candidate for the development of biofertilizer applicable to environmentally stressed soil. 相似文献
9.
Merja R. Häkkinen Mervi T. Hyvönen Seppo Auriola Robert A. Casero Jr Jouko Vepsäläinen Alex R. Khomutov Leena Alhonen Tuomo A. Keinänen 《Amino acids》2010,38(2):369-381
N-alkylated polyamine analogues have potential as anticancer and antiparasitic drugs. However, their metabolism in the host
has remained incompletely defined thus potentially limiting their utility. Here, we have studied the degradation of three
different spermine analogues N,N′-bis-(3-ethylaminopropyl)butane-1,4-diamine (DESPM), N-(3-benzyl-aminopropyl)-N′-(3-ethylaminopropyl)butane-1,4-diamine (BnEtSPM) and N,N′-bis-(3-benzylaminopropyl)butane-1,4-diamine (DBSPM) and related mono-alkylated derivatives as substrates of recombinant
human polyamine oxidase (APAO) and spermine oxidase (SMO). APAO and SMO metabolized DESPM to EtSPD [K
m(APAO) = 10 μM, k
cat(APAO) = 1.1 s−1 and K
m(SMO) = 28 μM, k
cat(SMO) = 0.8 s−1, respectively], metabolized BnEtSPM to EtSPD [K
m(APAO) = 0.9 μM, k
cat(APAO) = 1.1 s−1 and K
m(SMO) = 51 μM, k
cat(SMO) = 0.4 s−1, respectively], and metabolized DBSPM to BnSPD [K
m(APAO) = 5.4 μM, k
cat(APAO) = 2.0 s−1 and K
m(SMO) = 33 μM, k
cat(SMO) = 0.3 s−1, respectively]. Interestingly, mono-alkylated spermine derivatives were metabolized by APAO and SMO to SPD [EtSPM K
m(APAO) = 16 μM, k
cat(APAO) = 1.5 s−1; K
m(SMO) = 25 μM, k
cat(SMO) = 8.2 s−1; BnSPM K
m(APAO) = 6.0 μM, k
cat(APAO) = 2.8 s−1; K
m(SMO) = 19 μM, k
cat(SMO) = 0.8 s−1, respectively]. Surprisingly, EtSPD [K
m(APAO) = 37 μM, k
cat(APAO) = 0.1 s−1; K
m(SMO) = 48 μM, k
cat(SMO) = 0.05 s−1] and BnSPD [K
m(APAO) = 2.5 μM, k
cat(APAO) = 3.5 s−1; K
m(SMO) = 60 μM, k
cat(SMO) = 0.54 s−1] were metabolized to SPD by both the oxidases. Furthermore, we studied the degradation of DESPM, BnEtSPM or DBSPM in the
DU145 prostate carcinoma cell line. The same major metabolites EtSPD and/or BnSPD were detected both in the culture medium
and intracellularly after 48 h of culture. Moreover, EtSPM and BnSPM were detected from cell samples. Present data shows that
inducible SMO parallel with APAO could play an important role in polyamine based drug action, i.e. degradation of parent drug
and its metabolites, having significant impact on efficiency of these drugs, and hence for the development of novel N-alkylated polyamine analogues. 相似文献
10.
David van der Ha Sven Hoefman Pascal Boeckx Willy Verstraete Nico Boon 《Applied microbiology and biotechnology》2010,87(6):2355-2363
Effluents of anaerobic digesters are an underestimated source of greenhouse gases, as they are often saturated with methane.
A post-treatment with methane-oxidizing bacterial consortia could mitigate diffuse emissions at such sites. Semi-continuously
fed stirred reactors were used as model systems to characterize the influence of the key parameters on the activity of these
mixed methanotrophic communities. The addition of 140 mg L−1 NH4+–N had no significant influence on the activity nor did a temperature increase from 28°C to 35°C. On the other hand, addition
of 0.64 mg L−1 of copper(II) increased the methane removal rate by a factor of 1.5 to 1.7 since the activity of particulate methane monooxygenase
was enhanced. The influence of different concentrations of NaCl was also tested, as effluents of anaerobic digesters often
contain salt levels up to 10 g NaCl L−1. At a concentration of 11 g NaCl L−1, almost no methane-oxidizing activity was observed in the reactors without copper addition. Yet, reactors with copper addition
exhibited a sustained activity in the presence of NaCl. A colorimetric test based on naphthalene oxidation showed that soluble
methane monooxygenase was inhibited by copper, suggesting that the particulate methane monooxygenase was the active enzyme
and thus more salt resistant. The results obtained demonstrate that the treatment of methane-saturated effluents, even those
with increased ammonium (up to 140 mg L−1 NH4+–N) and salt levels, can be mitigated by implementation of methane-oxidizing microbial consortia. 相似文献
11.
Rosa María Camacho Juan Carlos Mateos-Díaz Dulce María Diaz-Montaño Orfil González-Reynoso Jesús Córdova 《Extremophiles : life under extreme conditions》2010,14(1):99-106
The capability of Halobacterium sp. NRC-1 to synthesize carboxyl ester hydrolases was investigated, and the effect of physicochemical conditions on the growth
rate and production of esterases was evaluated. The haloarchaeon synthesized a carboxyl ester hydrolase, confirming the genomic
prediction. This enzymatic activity was intracellularly produced as a growth-associated metabolite. Esterase activity was
assayed using different p-nitrophenyl-esters and triacyl-glycerides, which showed a preference for hydrolyzing tributyrin. The archaeal growth rate
and esterase production were significantly influenced by the pH and the NaCl concentration. An interaction effect between
temperature and NaCl was also seen. The maximal growth rate and esterase production found for Halobacterium sp. NRC-1 were 0.136 h−1 (at 4.2 M NaCl, pH 6 and 44°C) and 1.64 U/l (at 4.6 M NaCl, pH 6 and 30°C), respectively. Furthermore, the effects of NaCl
concentration, pH and temperature on enzyme activity were studied. Two maximal esterase activities were elucidated from the
intracellular crude extract when it was incubated at different NaCl concentrations (1 M and 5 M) and at different pHs (6 and
7.5). This is the first report that shows experimentally the synthesis of carboxyl ester hydrolases by Halobacterium sp. NRC-1. This enzyme was found to be extremely halophilic (5 M NaCl) and thermophilic (80°C), making it very interesting
for future investigations in non-aqueous biocatalysis. 相似文献
12.
Ethrel treatment enhanced isoflavonoids accumulation in cell suspension cultures of Pueraria tuberosa, a woody legume 总被引:1,自引:0,他引:1
The cell cultures of Pueraria tuberosa, a perennial leguminous lianas, were maintained in modified MS medium (KNO3 475 mg l−1, thiamine 1 mg l−1, biotin 1 mg l−1, calcium pantothenate 1 mg l−1) containing 0.1 mg l−1 2,4,5-trichloroacetic acid and 0.1 mg l−1 kinetin. Isoflavonoids (puerarin, genistin, daidzein, genistein) accumulation in cell suspension cultures was increased by
14-fold to ~12 mg l−1 after 48 h of adding 100 μM ethrel. Ethrel inhibitors (silver nitrate and silver thiosulfate) completely inhibited this effect
in the presence of ethrel and isoflavonoids were not detected in the spent medium. The increase was dose dependent and can
be explored to trigger high yield of isoflavonoids production. 相似文献
13.
Mammalian NADPH-cytochrome P450 reductase (CPR) transfers electrons from NADPH to cytochrome P450 enzymes and other several
microsomal enzymes. It also catalyzes the one-electron reduction of many chemicals and drugs. Reduction of 5-cyano-2,3-ditolyl
tetrazolium chloride (CTC) by CPR was assessed as a method for monitoring CPR activity. The electrons released from NADPH
by CPR were transferred to CTC in the reaction medium, and CTC reduction activity could be assessed spectrophotometrically
and spectrofluorometrically. The reduction kinetics of CTC follows classical Michaelis–Menten kinetics (K
m = 50 μM, k
cat = 2,520 min−1). This method offers a continuous assay of the enzymatic activity of CPR.
D. H. Kim and S. K. Yim are contributed equally to this work. 相似文献
14.
Filtrates from crushed Moringa oleifera seeds were tested for their effects on growth and Photosystem II efficiency of the common bloom-forming cyanobacterium Microcystis aeruginosa. M. aeruginosa populations exhibited good growth in controls and treatments with 4- and 8-mg crushed Moringa seeds per liter, having similar growth rates of 0.50 (±0.01) per day. In exposures of 20- to 160-mg crushed Moringa seeds L−1, growth rates were negative and on average −0.23 (±0.05) .day−1. Presumably, in the higher doses of 20- to 160-mg crushed seeds per liter, the cyanobacteria died, which was supported by
a rapid drop in the Photosystem II efficiency (ΦPSII), while the ΦPSII was high and unaffected in 0, 4, and 8 mg L−1. High-density populations of M. aeruginosa (chlorophyll-a concentrations of ∼270 μg L−1) were reduced to very low levels within 2 weeks of exposure to ≥80-mg crushed seeds per liter. At the highest dosage of 160 mg L−1, the ΦPSII dropped to zero rapidly and remained nil during the course of the experiment (14 days). Hence, under laboratory conditions,
a complete wipeout of the bloom could be achieved. This is the first study that yielded evidence for cyanobactericidal activity
of filtrate from crushed Moringa seeds, suggesting that Moringa seed extracts might have a potential as an effect-oriented measure lessening cyanobacterial nuisance. 相似文献
15.
J. K. Sharma M. Yadav N. P. Singh K. D. S. Yadav 《Applied Biochemistry and Microbiology》2011,47(5):532-537
Extracellular secretion of lignin peroxidase from Pycnoporus sanguineus MTCC-137 in the liquid culture growth medium amended with lignin containing natural sources has been shown. The maximum secretion
of lignin peroxidase has been found in the presence of saw dust. The enzyme has been purified to homogeneity from the culture
filtrate of the fungus using ultrafiltration and anion exchange chromatography on DEAE-cellulose. The purified lignin peroxidase
gave a single protein band in sodium dodecylsulphate polyacrylamide gel electrophoresis corresponding to the molecular mass
40 kDa. The K
m, k
cat and k
cat/K
m values of the enzyme using veratryl alcohol and H2O2 as the substrate were 61 M, 2.13 s−1, 3.5 × 104 M−1s−1 and 71 M, 2.13 s−1, 3.0 × 104 M−1 s−1 respectively at the optimum pH of 2.5. The temperature optimum of the enzyme was 25°C. 相似文献
16.
The cashew fruit (Anacardium occidentale L.) has been used as a promising agricultural resource for the production of low-molecular weight (MW) hyaluronic acid (HA) (104–105 Da). The cashew juice is a rich source of vitamin C containing, 1.2–2.0 g L−1. This work explores the effects of the initial concentration of the ascorbate on the solid fermentation of the juice-moisturized
bagasse from the cashew apple fruit. The results show that the MW reduction of HA is proportional to the initial ascorbate concentration. The presence of ascorbate did not influence the Streptococcus zooepidemicus metabolism. However, the HA productivity was increased from 0.18 to 0.28 mg g−1 h−1 when the ascorbate concentration ranged from 1.7 to 10 mg mL−1. These findings contribute to the controlled production of HA in a low MW range, which is important in cell signalization, angiogenesis and nanoparticles production. 相似文献
17.
The α-amylase encoding gene from acidophilic bacterium Bacillus acidicola was cloned into pET28a(+) vector and expressed in Escherichia coli BL21 (DE3). The recombinant E. coli produced a 15-fold higher α-amylase than B. acidicola strain. The recombinant α-amylase was purified to homogeneity by one-step nickel affinity chromatography using Ni2+-NTA resin with molecular mass of 62 KDa. It is active in the pH range between 3.0 and 7.0 and 30 and 100 °C with optimum
at pH 4.0 and 60 °C. The enzyme is Ca2+-independent with K
m and k
cat values (on soluble starch) of 1.6 mg ml−1 and 108.7 s−1, respectively. The α-amylase of B. acidicola is acidstable, high maltose forming and Ca2+-independent, and therefore, is a suitable candidate for starch hydrolysis and baking. 相似文献
18.
Cell cultures of Cayratia trifolia (Vitaceae), a tropical lianas, were maintained in Murashige and Skoog’s medium containing 0.25 mg l−1 NAA, 0.2 mg l−1 kinetin and casein hydrolysate 250 mg l−1. Cell suspension cultures of C. trifolia accumulate stilbenes (piceid, resveratrol, viniferin, ampelopsin), which on elicitation by any of 500 μM salicylic acid,
100 μM methyl jasmonate, 500 μM ethrel and 500 mg l−1 yeast extract, added on the 7th day, were enhanced by 3- to 6-fold (5–11 mg l−1) by the 15th day. 相似文献
19.
20.
To overcome the extracellular salt stress, Methanohalophilus portucalensis FDF1T synthesizes the compatible solute betaine through the methylation of glycine, sarcosine, and N,N-dimethylglycine. S-adenosylmethionine (AdoMet) is the methyl donor. The enzyme sarcosine dimethylglycine N-methyltransferase (SDMT) of M. portucalensis, that catalyzes the formation of N,N-dimethylglycine and glycine betaine, has been purified and characterized. SDMT, a monomer of 33 kDa with a pI at 5.03, has
a narrow substrate specificity limited to using only sarcosine and dimethylglycine as substrates for the methyl transferase
reaction. The K
m values for sarcosine and AdoMet were 2.29 and 0.21 mM, respectively, with a V
max of 0.83 μmol/mg-min (k
cat value of 0.44 s−1). The K
m values for dimethylglycine and AdoMet were 3.76 and 0.59 mM, respectively, with a V
max of 4.88 μmol/mg-min (k
cat of 2.68 s−1). A high concentration of the end product betaine (2.0 M) did not affect the SMT activity, but it slightly inhibited the
DMT activity. Both activities were also not affected by potassium or sodium ions in concentrations of 200–1,000 mM. We compared
this novel archaeal SDMT enzyme to other similar bacterial transferases as well as to the glycine sarcosine dimethylglycine
methyltransferase found also in M. portucalensis. 相似文献