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1.
Setlow B Cabrera-Hernandez A Cabrera-Martinez RM Setlow P 《Archives of microbiology》2004,181(1):60-67
Four aryl-phospho--d-glucosidases were identified in Bacillus subtilis by using 4-methylumbelliferyl-phospho--d-glucopyranoside as a substrate. Two of these enzymes are the products of the bglA and bglH genes, previously suggested to encode aryl-phospho--d-glucosidases, while the other enzymes are encoded by the yckE and ydhP genes. Together, these four genes account for >99.9% of the glucosidase activity in B. subtilis on aryl-phospho--d-glucosides. yckE was expressed at a low and constant level during growth, sporulation, and spore germination, and was not induced by aryl--d-glucosides. ydhP was also not induced by aryl--d-glucosides. However, while ydhP was expressed at only a very low level in exponential-phase cells and germinating spores, this gene was expressed at a higher levels upon entry into the stationary phase of growth. Strains lacking yckE or ydhP exhibited no defects in growth, sporulation, or spore germination or in growth on aryl--d-glucosides. However, a strain lacking bglA, bglH and yckE grew poorly if at all on aryl--d-glucosides as the sole carbon source.Abbreviations
MU
4-Methylumbelliferone
-
MUG
4-Methylumbelliferyl--d-glucopyranoside
-
MUGal
4-Methylumbelliferyl--d-galactopyranoside
-
MUG-P
4-Methylumbelliferyl--d-glucopyranoside-6-phosphate 相似文献
2.
Flax seed mucilage (FM) contains a mixture of highly doubly substituted arabinoxylan as well as rhamnogalacturonan I with
unusual side group substitutions. Treatment of FM with a GH11 Bacillus subtilis XynA endo 1,4-β-xylanase (BsX) gave limited formation of reducing ends but when BsX and FM were incubated together on different
wheat arabinoxylan substrates and birchwood xylan, significant amounts of xylose were released. Moreover, arabinose was released
from both water-extractable and water-unextractable wheat arabinoxylan. Since no xylose or arabinose was released by BsX addition
alone on these substrates, nor without FM or BsX addition, the results indicate the presence of endogenous β-d-xylosidase and α-l-arabinofuranosidase activities in FM. FM also exhibited activity on both p-nitrophenyl α-l-arabinofuranoside (pNPA) and p-nitrophenyl β-d-xylopyranoside (pNPX). Based on K
M
values, the FM enzyme activities had a higher affinity for pNPX (K
M
2 mM) than for pNPA (K
M
20 mM). 相似文献
3.
Kapil Tahlan Marcus A. Moore Susan E. Jensen 《Journal of industrial microbiology & biotechnology》2017,44(4-5):517-524
The δ-(l-α-aminoadipyl)-l-cysteinyl-d-valine (ACV) tripeptide is the first dedicated intermediate in the biosynthetic pathway leading to the penicillin and cephalosporin classes of β-lactam natural products in bacteria and fungi. It is synthesized nonribosomally by the ACV synthetase (ACVS) enzyme, which has been purified and partially characterized from many sources. Due to its large size and instability, many details regarding the reaction mechanism of ACVS are still not fully understood. In this review we discuss the chronology and associated methodology that led to the discovery of ACVS, some of the main findings regarding its activities, and some recent/current studies being conducted on the enzyme. In addition, we conclude with perspectives on what can be done to increase our understating of this very important protein in the future. 相似文献
4.
Lesław B. Lahuta Joanna Goszczyńska Marcin Horbowicz Czesław Hołdyński Ryszard J. Górecki 《Acta Physiologiae Plantarum》2010,32(5):933-942
The mechanism preferentially regulating accumulation of raffinose family oligosaccharides (RFOs) or galactosyl cyclitols in
legume seeds still remains unknown. The broad range of raffinose family oligosaccharides and galactosyl pinitols in the composition
of seeds of Vicia genus gives researchers an exceptional opportunity for investigations on relationships in biosynthesis of both types of α-d-galactosides. Feeding explants of Vicia species radically different in the composition of RFOs and galactosyl pinitols with basic galactose acceptors, sucrose (for
RFOs) or cyclitols (for galactosyl cyclitols) can be a helpful method for assessment of their regulatory role in accumulation
of α-d-galactosides in seeds. Garden vetch (Vicia sativa L.) seeds, naturally accumulating RFOs, demonstrated an ability to take up and use exogenously applied d-pinitol and d-chiro-inositol for synthesis of their mono-, di- and tri-galactosides. Together with the accumulation of new galactosides, the
concentration of RFOs decreased. In fine-leaved (Vicia tenuifolia Roth.) vetch seeds such a remarkably high concentration of galactosyl pinitols (GPs) was discovered that they nearly replaced
RFOs, which is unique among legumes. If the accumulation of both types of galactosides is correlated with concentration of
galactose acceptors, elevated levels of sucrose or myo-inositol should promote accumulation of RFOs, instead of GPs. Unexpectedly, feeding fine-leaved vetch raceme explants with
myo-inositol or sucrose promoted accumulation of GPs, but not of RFOs. Our comparison of accumulation and biosynthesis of both
types of galactosides (RFOs and GPs) throughout development and maturation of seeds from fine-leaved vetch has indicated that
preferential accumulation of GPs is associated with the drying of seeds during maturation. Different patterns in activities
of enzymes engaged in RFOs’ biosynthetic pathway and galactosyltransferases involved in biosynthesis of GPs indicated that
distinct forms of enzymes can operate in both pathways. The feeding of explants with d-chiro-inositol causes accumulation of fagopyritols B1 in seeds of both Vicia species, which suggests presence of the same or a similar form of galactinol synthase. Accumulation of fagopyritols in fine-leaved
vetch seeds did not affect accumulation of RFOs or galactosyl pinitols. 相似文献
5.
Takashi Kobayashi Taro Ehara Takanori Mizuoka Shuji Adachi 《Biotechnology letters》2010,32(11):1679-1684
In order to synthesize a sugar ester at high concentration, 1,2-O-isopropylidene-α-d-glucofuranose (IpGlc), which is one of the sugar acetals and is more hydrophobic than unmodified glucose, was esterified
with palmitic acid at 40°C using immobilized lipase from Candida antarctica in some organic solvents or their mixtures. Acetone + t-butyl alcohol (3:1 v/v) improved both the initial reaction rate and yield after 80 h: the product reached its maximum value
(240 mmol/kg solvent; ca. 110 g/kg solvent) when 400 mmol IpGlc/kg solvent and 1,200 mmol palmitic acid/kg solvent were used
in this solvent mixture. 相似文献
6.
Cobucci-Ponzano B Conte F Rossi M Moracci M 《Extremophiles : life under extreme conditions》2008,12(1):61-68
Glycoside hydrolases form hyperthermophilic archaea are interesting model systems for the study of catalysis at high temperatures
and, at the moment, their detailed enzymological characterization is the only approach to define their role in vivo. Family
29 of glycoside hydrolases classification groups α-l-fucosidases involved in a variety of biological events in Bacteria and Eukarya. In Archaea the first α-l-fucosidase was identified in Sulfolobus solfataricus as interrupted gene expressed by programmed −1 frameshifting. In this review, we describe the identification of the catalytic
residues of the archaeal enzyme, by means of the chemical rescue strategy. The intrinsic stability of the hyperthermophilic
enzyme allowed the use of this method, which resulted of general applicability for β and α glycoside hydrolases. In addition,
the presence in the active site of the archaeal enzyme of a triad of catalytic residues is a rather uncommon feature among
the glycoside hydrolases and suggested that in family 29 slightly different catalytic machineries coexist. 相似文献
7.
A lectin present in seeds of Clitoria ternatea agglutinated trypsin-treated human B erythrocytes. The sugar specificity assay indicated that lectin belongs to Gal/Gal NAc-specific
group. Hence the lectin, designated C. ternatea agglutinin (CTA), was purified by the combination of acetic acid precipitation, salt fractionation and affinity chromatography.
HPLC gel filtration, SDS-polyacrylamide gel electrophoresis and mass spectrometry indicated that the native lectin is composed
of two identical subunits of molecular weight 34.7 kDa associated by non covalent bonds. The N-terminal sequence of CTA shared
homology with Glycine max and Pisum sativum. Complete sequence was also found to be homologous to S-64 protein of Glycine max, suggesting that CTA probably exhibits both hemagglutination and probably sugar uptake activity. The carbohydrate binding
specificity of the lectin was investigated by quantitative turbidity measurements, and percent inhibition assays. Based on
these assays, we conclude that CTA binds β-d-galactosides, and also may has an extended specificity towards non-reducing terminal Neu5Acα2,6Gal. 相似文献
8.
l-β-Haloalanines are physiologically active unnatural amino acids and they are useful intermediates for the synthesis of natural
and unnatural amino acids, S-linked glycopeptides, and lanthionines. In general l-β-haloalanines were prepared predominantly from l-serine via functional group transformation. Here we reported an alternative approach for the preparation of l-β-haloalanines via halogenation of protected l-cysteine esters which was obtained from l-cysteine or l-cystine, respectively. The mercapto group of protected l-cysteine esters was efficiently transformed to halo groups by triphenylphosphine/N-halosuccinimides. It has been proved to be a versatile desulfurization strategy via this functional group transformation. 相似文献
9.
Carla Oliveira Sofia Costa José A. Teixeira Lucília Domingues 《Molecular biotechnology》2009,43(3):212-220
cDNA clones encoding frutalin, the α-d-galactose-binding lectin expressed in breadfruit seeds (Artocarpus incisa), were isolated and sequenced. The deduced amino acid sequences indicated that frutalin may be encoded by a family of genes.
The NCBI database searches revealed that the frutalin sequence is highly homologous with jacalin and mornigaG sequences. Frutalin
cDNA was re-amplified and cloned into the commercial expression vector pET-25b(+) for frutalin production in Escherichia coli. An experimental factorial design was employed to maximise the soluble expression of the recombinant lectin. The results
indicated that temperature, time of induction, concentration of IPTG and the interaction between the concentration of IPTG
and the time of induction had the most significant effects on the soluble expression level of recombinant frutalin. The optimal
culture conditions were as follows: induction with 1 mM IPTG at 22°C for 20 h, yielding 16 mg/l of soluble recombinant frutalin.
SDS-PAGE and Western blot analysis revealed that recombinant frutalin was successfully expressed by bacteria with the expected
molecular weight (17 kDa). These analyses also showed that recombinant frutalin was mainly produced as insoluble protein.
Recombinant frutalin produced by bacteria revealed agglutination properties and carbohydrate-binding specificity similar to
the native breadfruit lectin. 相似文献
10.
Clausen MH Ralet MC Willats WG McCartney L Marcus SE Thibault JF Knox JP 《Planta》2004,219(6):1036-1041
We report the isolation and characterization of a monoclonal antibody, designated LM9, against feruloylated-(14)--d-galactan. This epitope is a structural feature of cell wall pectic polysaccharides of plants belonging to the family Amaranthaceae (including the Chenopodiaceae). Immuno-assays and immunofluorescence microscopy indicated that LM9 binding is specific to samples and cell walls obtained from species belonging to this family. In a series of competitive-inhibition enzyme-linked immunosorbent assays with potential oligosaccharide haptens, the most effective inhibitor was O-[6-O-(trans-feruloyl)--d-galactopyranosyl]-(14)-d-galactopyranose (Gal2F). LM9 is therefore a useful antibody probe for the analysis of phenolic substitution of cell wall pectic polymers and of cell wall structure in the Amaranthaceae including sugar beet (Beta vulgaris L.) and spinach (Spinacia oleracea L.).Abbreviations DA Degree of acetylation - DM Degree of methyl esterification - ELISA Enzyme-linked immunosorbent assay - IDA Immunodot assay 相似文献
11.
Soria F Ellenrieder G Oliveira GB Cabrera M Carvalho LB 《Applied microbiology and biotechnology》2012,93(3):1127-1134
α-l-Rhamnosidase from Aspergillus terreus was covalently immobilized on the following ferromagnetic supports: polyethylene terephthalate (Dacron-hydrazide), polysiloxane/polyvinyl
alcohol (POS/PVA), and chitosan. The powdered supports were magnetized by thermal coprecipitation method using ferric and
ferrous chlorides, and the immobilization was carried out via glutaraldehyde. The activity of the Dacron-hydrazide (0.53 nkat/μg
of protein) and POS/PVA (0.59 nkat/μg of protein) immobilized enzyme was significantly higher than that found for the chitosan
derivative (0.06 nkat/μg of protein). The activity–pH and activity–temperature profiles for all immobilized enzymes did not
show difference compared to the free enzyme, except the chitosan derivative that presented higher maximum temperature at 65 °C.
The Dacron-hydrazide derivative thermal stability showed a similar behavior of the free enzyme in the temperature range of
40–70 °C. The POS/PVA and chitosan derivatives were stable up to 60 °C, but were completely inactivated at 70 °C. The activity
of the preparations did not appreciably decrease after ten successive reuses. Apparent K
m of α-l-rhamnosidase immobilized on magnetized Dacron-hydrazide (1.05 ± 0.22 mM), POS/PVA (0.57 ± 0.09 mM), and chitosan (1.78 ± 0.24 mM)
were higher than that estimated for the soluble enzyme (0.30 ± 0.03 mM). The Dacron-hydrazide enzyme derivative showed better
performance than the free enzyme to hydrolyze 0.3% narigin (91% and 73% after 1 h, respectively) and synthesize rhamnosides
(0.116 and 0.014 mg narirutin after 1 h, respectively). 相似文献
12.
Jordan DB Wagschal K Fan Z Yuan L Braker JD Heng C 《Journal of industrial microbiology & biotechnology》2011,38(11):1821-1835
β-d-Xylosidase/α-l-arabinofuranosidase from Selenomonas ruminantium is the most active enzyme reported for catalyzing hydrolysis of 1,4-β-d-xylooligosaccharides to d-xylose. One property that could use improvement is its relatively high affinities for d-glucose and d-xylose (K
i ~ 10 mM), which would impede its performance as a catalyst in the saccharification of lignocellulosic biomass for the production
of biofuels and other value-added products. Previously, we discovered that the W145G variant expresses K
i
d-glucose and K
i
d-xylose twofold and threefold those of the wild-type enzyme. However, in comparison to the wild type, the variant expresses 11% lower
k
cat
d-xylobiose and much lower stabilities to temperature and pH. Here, we performed saturation mutagenesis of W145 and discovered that the
variants express K
i values that are 1.5–2.7-fold (d-glucose) and 1.9–4.6-fold (d-xylose) those of wild-type enzyme. W145F, W145L, and W145Y express good stability and, respectively, 11, 6, and 1% higher
k
cat
d-xylobiose than that of the wild type. At 0.1 M d-xylobiose and 0.1 M d-xylose, kinetic parameters indicate that W145F, W145L, and W145Y catalytic activities are respectively 46, 71, and 48% greater
than that of the wild-type enzyme. 相似文献
13.
Tada R Tanioka A Iwasawa H Hatashima K Shoji Y Ishibashi K Adachi Y Yamazaki M Tsubaki K Ohno N 《Glycoconjugate journal》2008,25(9):851-861
A β-d-glucan obtained from Aureobasidium pullulans (AP-FBG) exhibits various biological activities: it exhibits antitumour and antiosteoporotic effects and prevents food allergies.
An unambiguous structural characterisation of AP-FBG is still awaited. The biological effects of β-d-glucan are known to depend on its primary structures, conformation, and molecular weight. Here, we elucidate the primary
structure of AP-FBG by NMR spectroscopy, and evaluate its biological activities. Its structure was shown to comprise a mixture
of a 1-3-β-d-glucan backbone with single 1-6-β-d-glucopyranosyl side-branching units every two residues (major structure) and a 1-3-β-d-glucan backbone with single 1-6-β-d-glucopyranosyl side-branching units every three residues (minor structure). Furthermore, this β-d-glucan exhibited immunostimulatory effects such as the accumulation of immune cells and priming effects against enterobacterium.
To our knowledge, 1-3-β-glucans like AP-FBG with such a high number of 1-6-β-glucopyranosyl side branching have a unique structure;
nevertheless, many 1-3-β-glucans were isolated from various sources, e.g. fungi, bacteria, and plants. 相似文献
14.
Xiao-Qiang Qi Qing-Li Sun Li-Ping Bai Jun-Jie Shan Yang Zhang Ren Zhang Yuan Li 《Applied microbiology and biotechnology》2009,83(2):361-368
Ebosin, a novel exopolysaccharide produced by Streptomyces sp. 139 has antagonist activity for IL-1R in vitro and remarkable anti-rheumatic arthritis activity in vivo. Its biosynthesis
gene cluster (ste) has been identified. In this study, gene ste17 was expressed in Escherichia coli BL21 and the recombinant protein was purified. With CTP and α-d-glucose-1-phosphate as substrates, the recombinant Ste17 protein was found capable of catalyzing the production of CDP-d-glucose and pyrophosphate, demonstrating its identity as an α-d-glucose-1-phosphate–cytidylyltransferase (CDP-d-glucose synthase). To investigate the function of ste17 in Ebosin biosynthesis, the gene was disrupted with a double crossover via homologous recombination. The monosaccharide composition
of exopolysaccharide (EPS) produced by the mutant Streptomyces sp. 139 (ste17
−) was found significantly altered from that of Ebosin, with glucose becoming undetectable. This gene knockout also negatively
affected the antagonist activity for IL-1R of EPS. These results indicate that the CDP-d-glucose synthase encoded by ste17 gene is involved in the formation of nucleotide sugar (CDP-d-glucose) as glucose precursor in Ebosin biosynthesis.
Xiao-Qiang Qi and Qing-Li Sun contributed equally to this work. 相似文献
15.
Thermomonospora fusca produced a relatively high level of alpha-L-arabinofuranosidase when growing on oat spelt xylan as the main carbon and energy source. The enzyme exhibited maximum relative activity (0.136 U/g protein) at pH 9.0 with 54 and 55% activity remaining at pH of 4.5 and 11.0, respectively. The apparent Km value for the crude alpha-L-arabinofuranosidase preparation was 180 mumol/L 4-nitrophenyl alpha-L-arabinofuranoside; the upsilon lim value was the release of 40 mumol/L 4-nitrophenol per min. Enzyme activity was eluted as a single peak (HPLC gel filtration chromatography) corresponding to molar mass of approximately 92 kDa. Native electrophoresis of crude cell lysate confirmed the presence of a single active intracellular alpha-L-arabinofuranosidase component. SDS-PAGE of this enzyme, developed as zymogram, did not demonstrate any activity; denaturing gel was stained and a protein band of relative molar mass of 46 kDa was revealed. Isoelectric focusing of a purified alpha-L-arabinofuranosidase yielded a single protein band for the corresponding activity zone with pI 7.9. The enzyme was purified approximately 21-fold the mean overall yield was about 16%. 相似文献
16.
de Wet BJ Matthew MK Storbeck KH van Zyl WH Prior BA 《Applied microbiology and biotechnology》2008,77(5):975-983
A glycosyl hydrolase family 54 (GH54) α-l-arabinofuranosidase gene (abfA) of Aureobasidium pullulans was amplified by polymerase chain reaction from genomic DNA and a 498-amino-acid open reading frame deduced from the DNA
sequence. Modeling of the highly conserved A. pullulans AbfA protein sequence on the crystal structure of Aspergillus kawachii AkabfB showed that the catalytic amino acid arrangement and overall structure were highly similar including the N-terminal
catalytic and C-terminal arabinose binding domains. The abfA gene was expressed in Saccharomyces cerevisiae, and the heterologous enzyme was purified. The protein was monomeric, migrating at 49 kDa on sodium dodecyl sulfate-polyacrylamide
gel electrophoresis and eluting at 36 kDa upon gel filtration. AbfA showed maximal activity at 55°C and between pH 3.5 and
pH 4. The enzyme had a K
m value for p-nitrophenyl-α-l-arabinofuranoside of 3.7 mM and a V
max of 34.8 μmol min−1 mg protein−1. Arabinose acted as a noncompetitive inhibitor with a K
i of 38.4 mM. The enzyme released arabinose from maize fiber, oat spelt arabinoxylan, and wheat arabinoxylan, but not from
larch wood arabinogalactan or α-1,5-debranched arabinan. AbfA displayed low activity against α-1,5-l-arabino-oligosaccharides. The enzyme acted synergistically with endo-β-1,4-xylanase in the breakdown of wheat arabinoxylan. Binding of AbfA to xylan from several sources confirmed the presence
of a functional carbohydrate-binding module.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
17.
Anne Mette Madsen Margit Wagtberg Frederiksen Leila Allermann Jan Hyld Peitersen 《Aerobiologia》2011,27(2):173-179
This study was undertaken to investigate how the length of the extraction period influences the (1 → 3)-β-d-glucan (β-glucan) yield and also to examine the background concentration of β-glucan as airborne β-glucan in outdoor environments
in different seasons and as concentrations in airborne and floor dust in offices. To ensure compatibility between results
obtained in different laboratories, it is important to use optimal and standardised methods to extract and quantify β-glucan.
In this study, an extraction period of 60 min gave the highest β-glucan yield. The median concentration of β-glucan in 44
floor dust samples was 597 μg g−1 dust. The median concentration of airborne β-glucan in offices was 5.1 ng m−3 in the summer and 2.3 ng m−3 in the winter, and the outdoor median concentration in towns was 6.8 ng m−3. The outdoor airborne concentration of β-glucan was significantly lower in January, November and December than during the
rest of year. In July, the median airborne concentration of β-glucan was 14 times higher than in January. Furthermore, the
airborne concentration of β-glucan was significantly higher in July than in March, April, May, September and October. In the
summertime, we found that the indoor airborne concentration of β-glucan was lower than outdoor concentrations. This is in
accordance with measurements of concentrations of airborne pollen and culturable fungal spores showing higher outdoor than
indoor concentrations during the summer months. 相似文献
18.
Jung KH Yeon JH Moon SK Choi JH 《Journal of industrial microbiology & biotechnology》2008,35(7):695-701
19.
Biocatalytic acylation of 1-β-d-arabinofuranosylcytosine (ara-C) was developed using whole cell of Aspergillus oryzae as a novel catalyst. 13C nuclear magnetic resonance (NMR) analysis indicated that the whole-cell biocatalyst had more specific activity toward the
3′-hydroxyl group than 5′-hydroxyl group among the available hydroxyl groups in sugar moiety of ara-C. Except for glucose
and maltose, 11 carbon sources supplemented to basal media, including Spans, Tweens, olive oil and oleic acid, exhibited notable
enhancement effects on both the cell growth and the acylation reactions. It was suggested that the carbon sources containing
controlled-release oleic acid were the important substrates for the production of fungal cell-bound lipase with specific activity,
partially due to a gradual induction effect of their released oleic acid on the cell-bound lipase production. Despite the
low initial reaction rate and substrate conversion, the addition of 2.0 g/l Span 80 resulted in a higher 3′-regioselectivity
of the cells than 81%. By using Tween 85 at its optimum concentration of 5.0 g/l, however, the highest initial rates (3.2 mmol/l h)
and substrate conversion (76%) of the whole-cell catalyzed acylation of ara-C can be achieved. It was also found that the
3′-regioselectivity of the cells showed observable increase by extending the culture time. And the activity of cell-bound
lipase drastically increased in the early stage of cell growth and then declined in the late culture stage, whatever the culture
media used. Our results thus indicated that A. oryzae whole cell was a promising green tool for biosynthesis of nucleoside esters with potential bioactivities. 相似文献
20.
β-N-Methylamino-l-alanine (BMAA), a non-proteinogenic amino acid, has been detected in a range of cyanobacteria, including terrestrial, aquatic,
free living and endosymbiotic species. The widespread occurrence of cyanobacteria in the environment raises concerns regarding
the ecological and toxicological impact of BMAA, and consequently, studies have focussed extensively on the toxicity and environmental
impact of BMAA, while no research has addressed the ecophysiological or metabolic role of the compound in cyanobacteria. In
this study, both the uptake of exogenous BMAA by and the effect of exogenous BMAA on the growth of Synechocystis PCC6803 were investigated. BMAA was rapidly taken up by the non-diazotrophic cyanobacterium Synechocystis PCC6803 in a concentration dependent manner. The presence of exogenous BMAA resulted in a substantial and concentration-dependent
decrease in cell growth and the substantial loss of photosynthetic pigmentation. Similar effects were seen in the presence
of the non-proteinogenic amino acid, 2,4-diaminobutyric acid but to a lesser degree than that of BMAA. The effects were reversed
when light was decreased from 16 to 10 μmol m−2 s−1. Control cultures grown in the presence of l-arginine, l-asparagine, l-glutamate and glycine showed normal or slightly increased growth with no change in pigmentation. The decrease in growth rate
coupled to bleaching indicates that BMAA may induce chlorosis in the presence of adequate photosynthetic radiation suggesting
a connection between BMAA and the induction of conditions, such as nitrogen or sulphur depletion, that result in growth arrest
and the induction of chlorosis. 相似文献