共查询到20条相似文献,搜索用时 31 毫秒
1.
Toshikazu Oki Akihiro Yoshimoto Tatsuo Ogasawara Seiji Sato Akira Takamatsu 《Archives of microbiology》1976,107(2):183-187
The occurrence of adenosine 5-triphosphate-3-diphosphate-synthesizing activity was detected in five strains of actinomycetes; Streptomyces morookaensis, Streptomyces aspergilloides, Streptomyces hachijoensis, Actinomyces violascens and Streptoverticillium septatum, out of 825 strains of actinomycetes, bacteria, fungi and imperfecti. Purine nucleotide pyrophosphotransferase were extracellularly excreted associating with the cell growth, and were purified partially or to apparent homogeniety from the culture filtrate. The enzymes are a monomeric protein with a molecular weight of 18000–26000 and synthesize adenosine, guanosine and inosine 5-phosphate (mono, di or tri)-3-diphosphate such as pApp, ppApp, pppApp, pGpp, ppGpp, pppGpp and pppIpp by transferring a pyrophosphoryl group from the 5-position of ATP, dATP and pppApp to the 3-position of purine nucleotides in the presence of a divalent cation and in alkaline state.Abbreviations pppApp
adenosine 5-triphosphate 3-diphosphate
- ppApp
adenosine 5-diphosphate 3-diphosphate
- pApp
adenosine 5-monophosphate 3-diphosphate
- pppGpp
guanosine 5-triphosphate 3-diphosphate 相似文献
2.
Bellizzi Mary C. Dutta-Roy Asim K. James W. Philip T. 《Molecular and cellular biochemistry》1997,170(1-2):187-193
The role of -tocopherol uptake system in human erythrocyte in the uptake of plasma -tocopherol has been suggested. However no information is available on -tocopherol uptake activity of human erythrocytes in the presence of high levels of D-glucose which is known to lead to pathological alterations in different cells including human erythrocytes. Therefore, in order to examine the effect of D-glucose on the binding of -tocopherol to human erythrocytes, the binding characteristics of -tocopherol to these cells were established first. Binding of [3H]-tocopherol to human erythrocytes was both saturable and specific. Scatchard analysis of -tocopherol binding to these cells showed the presence of two independent classes of binding sites with widely different affinities. The high affinity binding sites had a dissociation constant (Kd1) of 90 nM with a binding capacity (n1) of 900 sites per cell, whereas the low affinity binding sites had a dissociation constant (Kd2) of 5.2 M and a binding capacity (n2) of 105,400 sites per cell. Trypsin treatment abolished all the -tocopherol binding activity. Competition for the binding of -tocopherol to human erythrocytes was effective with other homologues of -tocopherol (-tocopherol, -tocopherol and -tocopherol) and their potency was almost equal to -tocopherol itself. The order of preference was -tocopherol > -tocopherol -tocopherol -tocopherol. Incubation of human erythrocytes with various concentrations of D-glucose did not affect -tocopherol uptake activity. Our data demonstrate the presence of an -tocopherol uptake system in human erythrocytes and that the -tocopherol uptake activity is not modulated by the presence of D-glucose. 相似文献
3.
Vincent T. K. Chow Meena K. Sakharkar D. P. P. Lim W. M. Yeo 《Biochemical genetics》2001,39(5-6):201-211
The coatomer complex is involved in intracellular protein transport and comprises an assembly of seven polypeptide subunits designated , , , , , , and COP. Rooted phylogenetic trees constructed from the full-length cDNA and amino acid sequences of 49 COP entities in different eukaryotes from yeast to man generally revealed striking conservation of each subunit through evolution. Both nucleotide and protein trees displayed close relationships between and subunits, between and subunits, and between and subunits, implying evolution from common ancestors as well as functional similarity. Interestingly, although 6 out of 7 -COP genes appeared to be grouped and related to the -COP genes, 4 out of 7 -COP gene products clustered with other groups of other COP subunit proteins. A 5 coding segment of the murine -COP gene was amplified by RT-PCR and cycle-sequenced. The partial predicted amino acid sequence of this murine homolog was exactly identical to the human and bovine counterparts. Of particular significance was the complete identity of the first 25 and 35 N-terminal residues which constitute the gastrointestinal hormone xenin and its precursor proxenin, thus emphasizing their strict evolutionary conservation and alluding to their physiological importance. 相似文献
4.
I explore the specialization versus generalization paradigm in frugivory and seed dispersal. This view predicts that some tropical trees produce nutritious fruits adapted for use by a small coterie of specialized frugivores that provide reliable seed dissemination. Other tree species are expected to offer superabundant fruits of lower nutritional reward, relying instead on common opportunistic frugivores that are individually less reliable, but collectively disperse seeds effectively. Though widely referenced, many aspects of the paradigm are untested with tropical trees and avian frugivores, primarily because plant ecologists rarely determine whether specialist or generalist foragers are responsible for different patterns of seed distribution, while students of foraging behavior rarely determine the effects seed dispersal by different animals for survival of seeds or seedlings of specialist or generalist trees.Ecological paradigms provide alternative hypotheses, without evolutionary arguments. Keystone species have ecological effects disproportionate to their abundance; it is important for management considerations to know whether fruiting trees or frugivores serve as keystone mutualists in tropical forests. Alternatively, the extent to which vertebrate seed dispersers influence density-dependent seed, seedling, sapling, or adult mortality may have important consequences for spatial dispersion and population dynamics of tree species in tropical forests. 相似文献
5.
Summary Cyclic nucleotide phosphodiesterase in the basal-lateral segment of plasma membranes from proximal tubule cells of the rabbit renal cortex was studied and compared to that in the brush border segment of the plasma membrane. Both adenosine 3,5-monophosphate and guanosine 3,5-monophosphate were hydrolyzed by the basal-lateral membrane, but activity varied differently with the two substrates in a complex concentration-dependent manner. Activity with adenosine 3,5-monophosphate was greater than, equal to, or less than with guanosine 3,5-monophosphate, at concentrations of 1000, 100, and 10 to 1 m, respectively. Basal-lateral membrane phosphodiesterase activities at 1 and 500 m substrate exhibited differential responses to pH, metals, heat, and a heat stable inhibitor. Stimulation by guanosine 3,5-monophosphate and inosine 3,5-monophosphate of adenosine 3,5-monophosphate hydrolysis was found in basal-lateral but not in brush border membranes. This stimulation was potentiated by ethyleneglycol-bis(-aminoethyl ether)N,N-tetraacetic acid and ethylenediaminetetraacetate, inhibited by Triton X-100, and totally blocked by Zn2+. The findings indicate that multiple forms of phosphodiesterase are present in the basal-lateral segment and these differ from the activities in the brush border region of the plasma membrane. The characteristics of (i) allosteric, guanosine 3,5-monophosphate-sensitivity of adensoine 3,5-monophosphate phosphodiesterase, and (ii) relatively high guanosine 3,5-monophosphate phosphodiesterase activity, in basal-lateral membranes, which are also enriched in adenylate and guanylate cyclase, suggest an important physiological role for these phosphodiesterases in the regulation of net production of cyclic nucleotides in the renal cortex. 相似文献
6.
Zhiwu?Li Sarah?Meyer Juliane S.?Essig Ying?Liu Melissa A.?Schapaugh S.?Muthukrishnan Bryan E.?Hainline Harold N.?Trick
Primers were developed for 118 microsatellites isolated from grape (Vitis vinifera) genomic libraries enriched for (AC)n repeats. Only one microsatellite sequence matched other grape SSR-sequences in the GeneBank database. Genotyping was carried out in the parental lines and four offspring of two pseudo-test-cross populations, Cabernet Sauvignon x Seyval and Chardonnay x Bianca, and a further six other grape genotypes (V. vinifera Sultanina, Merlot, Syrah, Müller-Thurgau, Vitis Regent and V. riparia Gloire de Montpellier). A total of 108 microsatellites showed easily scorable alleles and 100 of them segregated according to a configuration suitable for mapping in either cross. A further 8 SSRs, although unsuitable for mapping in those crosses, showed polymorphism in the other genotypes tested. This set of markers was used, along with 75 microsatellites of other repeat-types, to fingerprint 46 offspring of the cross Chardonnay x Bianca. For each full-sib, individual heterozygosity and distance in repeat units between pairs of alleles at each locus (mean d2) were calculated as a tool for predicting highly outbred recombinant individuals. Six microsatellites with segregation ratios significantly distorted towards the lack of homozygous sibs were identified and mapped to linkage groups LG 3 and LG 5. Estimation of heterozygosity at genome-wide level and genotyping at loci for which homozygous sibs are discriminated against are discussed for marker-assisted background selection in outcrossing grapevines. 相似文献
7.
The continuous control of the maximum position of the dye absorption band (the zero of the derivative dD
()/d of the cell's optical density D
()) in a nematic matrix is demonstrated experimentally, as a result of changing the angle between the optical axis of a planar-oriented sample and the plane of polarization of absorbed light incident normal to the optical axis. The theory proposed describes quantitatively the experimental dependence (). The rotation of the polarizer with given frequency results in the spectral position modulation of the solute band maximum () within (=0°)–(90°)=700 cm–1. 相似文献
8.
Lutz Birnbaumer Ning Qin Riccardo Olcese Erwin Tareilus Daniela Platano Jim Costantin Enrico Stefani 《Journal of bioenergetics and biomembranes》1998,30(4):357-375
Calcium channel subunits have profound effects on how 1 subunits perform. In this article we summarize our present knowledge of the primary structures of subunits as deduced from cDNAs and illustrate their different properties. Upon co-expression with 1 subunits, the effects of subunits vary somewhat between L-type and non-L-type channels mostly because the two types of channels have different responses to voltage which are affected by subunits, such as long-lasting prepulse facilitation of 1C (absent in 1E) and inhibition by G protein dimer of 1E, absent in 1C. One subunit, a brain 2a splice variant that is palmitoylated, has several effects not seen with any of the others, and these are due to palmitoylation. We also illustrate the finding that functional expression of 1 in oocytes requires a subunit even if the final channel shows no evidence for its presence. We propose two structural models for Ca2+ channels to account for 1 alone channels seen in cells with limited subunit expression. In one model, dissociates from the mature 1 after proper folding and membrane insertion. Regulated channels seen upon co-expression of high levels of would then have subunit composition 1. In the other model, the chaperoning remains associated with the mature channel and 1 alone channels would in fact be 1 channels. Upon co-expression of high levels of the regulated channels would have composition [1]. 相似文献
9.
Shiro Tsuyuzaki 《Plant Ecology》1996,122(2):151-156
To evaluate alpha diversities, various variables such as density, cover, volume, and weight have been used. However, density is often a distinct variable from the remaining three. To clarify differences in diversity measured by those two kinds of variables, the data collected in fourteen 2×5 m permanently-marked plots on Mount Usu, Japan, which erupted during 1977 and 1978 in growing seasons from 1983 to 1989 was analyzed, using Shannon's species diversity (H) that is represented as a result of combination of species richness and evenness (J). H and J were evaluated by density (density H and J) and cover (cover H and J). Cover H and J were significantly lower than density H and J, indicating that cover H has different characteristics from density H. Those differences are due to differences in evenness, because species richness is the same. The rank orders of species density are different from those of cover. The predominance of a few perennial herbs greatly decreases cover evenness, while seedling establishment success influences density evenness. Therefore, I propose that, during the early stages of succession on harsh environments such as volcanoes, density diversity represents seedling establishment success rate while cover diversity expresses vegetative reproduction success rate. 相似文献
10.
Uldis Z. Kalnenieks Juris B. Saulitis Nina I. Galinina Edward E. Liepinś Juris E. Shivinka 《Archives of microbiology》1989,151(3):213-219
Brevibacterium flavum 22LD-P cells were shown to maintain a transmembrane pH gradient (pH) from 0.6 to 1.8–2 units and a transmembrane electric potential difference () from 0 to 200 mV depending on the pH and ionic composition of the incubation medium, grwoth substrate and concentration of cells. decreased from 120–140 mV to 0 when medium pH was lowered from neutral to 5.0–5.5 and increased to 180–200 mV when medium pH was raised to 8–9 in cells utilizing acetate or endogenous substrate. Cells growing on sucrose, kept around 100–120 mV at neutral as well as acidic medium pH. Intracellular pH in the acetate utilizing or endogenously respiring cells was maintained with the range of 8.9 to 5.5 at medium pH ranging from 9.1 to 4.0, respectively. Sucrose grown cells were able to maintain a more stable intracellular pH. Endogenously respiring cells in potassium phosphate buffer at high biomass concentrations maintained larger pH and relatively smaller , than the same cells in diluted suspensions. Cells in sodium phosphate buffer possessed larger and almost no pH, but was still dependent on biomass concentration.The lack of intracellular pH homeostasis and the collapse of at acid medium pH are discussed in the context of cell membrane proton permeability. 相似文献
11.
O. P. Rajora J. D. Mahon 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,89(2-3):206-210
Restriction fragment analysis was used to examine the inheritance of lentil mitochondrial DNA (mtDNA) in F1 and F5 progeny from intrasubspecific (Lens culinaris ssp. culinaris) crosses and in F1 progeny from intersubspecific (Lens culinaris ssp. orientalis x L. culinaris ssp. culinaris) crosses. Southern blots of digested parental and progeny DNA were hybridized to heterologous maize mtDNA probes specific to coxI and atp6 genes. Two restriction fragment polymorphisms separated L.c. ssp. culinaris Laird and Eston from L.c. ssp. culinaris ILL5588, and one restriction fragment polymorphism distinguished L.c. ssp. culinaris Laird and Eston from L.c. ssp. orientalis LO4. Twelve of 13 f1 progeny and all F5 progeny from the intrasubspecific crosses, and all F1 progeny from intersubspecific crosses had only maternal mtDNA restriction fragments. One f1 plant from an Eston x ILL5588 cross inherited mtDNA fragments from both parents. Nuclear DNA inheritance was biparental in all F1 progeny.NRCC No. 38451 相似文献
12.
Regio- and stereo-selective synthesis of vinyl glucose ester catalyzed by an alkaline protease of Bacillus subtilis 总被引:1,自引:0,他引:1
Qi Wu Deshui Lu Ying Cai Xingtao Xue Zhichun Chen Xianfu Lin 《Biotechnology letters》2001,23(24):1981-1985
The transesterification of -d-glucose with divinylsuccinate, divinyladipate and divinylsebacate in pyridine at 55 °C for 3 days was catalyzed by an alkaline protease from Bacillus subtilis to give corresponding 6-O-vinyl glucose esters at 30%, 53% and 35% yield, respectively. The stereo-selectivity of the alkaline protease toward the -anomer was affected by the acyl donor chain length. 6-O-Vinylsuccinyl-d-glucose was mixture of - and -anomers (/=44/56), the other two products were the pure -d-glucose derivatives. 相似文献
13.
Antti Seppo Leena Penttilä Anne Leppänen Hannu Maaheimo Ritva Niemelä Jari Helin Jean-Michel Wieruszeski Ossi Renkonen 《Glycoconjugate journal》1994,11(3):217-225
1,3-Galactosylation of radiolabelled bi-antennary acceptors Gal1-4GlcNAc1-3(Gal1-4GlcNAc1-6)Gal-R (R=1-OH, 1-4GlcNAc or 1-4Glc) with bovine thymus 1,3-galactosyltransferase was studied. At all stages of the reactions the three acceptors reacted faster at the 1 6 linked arm than at the 1 3 linked branch. Hence, in addition to the doubly 1,3-galactosylated products, practically pure Gal1-4GlcNAc1-3(Gal1-3Gal1-4GlcNAc1-6)Gal-R could be obtained from the three acceptors in reactions that had proceeded to near completion. The isomeric mono-1,3-galactosylated products were identified by using exoglycosidases to remove the branches unprotected by 1,3-galactoses and by subsequently identifying the resulting linear glycans chromatographically.Abbreviations Gal
d-galactose
- GlcNAc
N-acetyl-d-glucosamine
- Lac
lactose
- LacNAc
Gal1-4GlcNAc
- MH
maltoheptaose
- MP
maltopentaose
- MT
maltotriose
- MTet
maltotetraose
- WGA
wheat germ agglutinin
- 3
position 3 of the galactose unit of LacNAc or Lac
- 6
position 6 of the galactose unit of LacNAc or Lac 相似文献
14.
Konrad Huppi Evelyne Jouvin-Marche Cynthia Scott Michael Potter Martin Weigert 《Immunogenetics》1985,21(5):445-457
Variable (V) and constant (C) region genes of the mouse kappa light chain have been compared in inbred strains and in geographically isolated or genetically separated populations of mice by Southern blot analysis of endonuclease-restricted germline DNA. In most cases, the C gene is found on a single restriction fragment while the V genes of the V19 and V21 groups are each found on several (6–18) fragments. The restriction fragment (RF) patterns of V19 and V21 groups are both polymorphic when compared among inbred mouse strains. Southern blot patterns of V21 and V19 of inbred strains are also found among some geographically isolated populations of mice, suggesting that inbred strains acquired kappa loci from different subspecies. Some populations of geographical isolates show V21, V19, and C contexts similar to inbred mice while more distantly related species within the genus Mus and laboratory rats show no apparent similarity in context to inbred strains. Variable region genes determining the RF patterns of V19 and V21 appear to be linked to each other and to the C and Lyt-3 loci. 相似文献
15.
A simple one variable caricature for oscillating and excitable reaction-diffusion systems is introduced. It is shown that as a parameter, , varies the system dynamics change from oscillatory ( >
0) to excitable ( <
0) and the frequency of the oscillation vanishes as
for 0. When such dynamics are coupled by continuous diffusion in a ring geometry (1-space dimension), propagating wave trains may be found. On an infinite ring excitable devices lead to unique solitary waves which are analogous to pulse waves. A solvable example is presented, illustrating properties of dispersion, excitability, and waves. Finally it is shown that the caricature arises in a natural way from more general excitable/oscillatory systems. 相似文献
16.
E. C. Roumen 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1994,89(4):498-503
The inheritance of host plant resistance and its effect on the relative infection efficiency for leaf blast was studied in the crosses IR36/CO39 (partially resistant × highly susceptible) and IR36/IR64 (both partially resistant). On the natural scale, gene action appeared multiplicative. After log transformation, additive effects described most of the genetic variation in the cross IR36/CO39, while additive and dominance effects were about equal in magnitude in the cross IR36/IR64. Dominance was towards increased resistance. No transgressive segregation occurred in the cross IR36/CO39. The number of genes that reduce lesion number was estimated to be zero in CO39 and five or more in IR36. The cross IR36/IR64 showed transgressive segregation in both directions, and IR36 and IR64 each contain at least one gene that is not present in the other cultivar. The heritabilities (narrow sense) in the F2 were low (range 0.06–0.16), while narrow sense heritabilities based on F3 lines were much higher (range 0.41–0.68). Lesion numbers in F3 lines were reasonably correlated with those in F5 progenies derived from the same F2 plant (r was±0.6 in both crosses). Partial resistance can be effectively improved by selecting the most resistant plants from the most resistant F3 lines. 相似文献
17.
Eliezer E. Goldschmidt 《Plant Growth Regulation》1984,2(1):9-13
The relationship of abscisic acid (ABA) and 2-trans-abscisic acid (t-ABA) to alternate bearing has been examined in Wilking mandarin (Citrus reticulata Blanco) trees. Leaves, stems and buds of trees loaded with fruit (on trees) had 4.3, 6.0 and 2.2 fold higher ABA levels than the corresponding organs from off trees. Leaves had higher ABA levels than stems and buds in both on and off trees. t-ABA was non-detectable in Wilking leaf, stem and bud tissue. Amounts of t-ABA not exceeding 40% of the ABA content, were found in Shamouti and Valencia orange buds and in Wilking fruit peel.The elevated levels of ABA in on tree organs may reflect a stress imposed by the fruit overload. 相似文献
18.
Ischemia-reperfusion (I/R) injury is a complex process involving the generation and release of inflammatory cytokines, and the accumulation and infiltration of neutrophils and macrophages, which disturbs the microcirculatory hemodynamics. Nonetheless, ischemic preconditioning (IPC) is known to produce immediate tolerance to subsequent prolonged I/R insults, although its underlying mechanism largely remains unknown. Our study investigated the role of the IB--NF-B-TNF- (tumor necrosis factor-) pathway in IPC's ability to ameliorate I/R-induced microcirculatory disturbances in rat cremaster muscle flaps. Male Sprague-Dawley rats were randomized (n=8 per group) into 3 groups: a sham-operated control group, an I/R group (4 h of pudic epigastric artery ischemia followed by 2 h of reperfusion), and an IPC+I/R group (3 cycles of 10 min of ischemia followed by 10 min reperfusion before I/R). Intravital microscopy was used to observe leukocyte/endothelial cell interactions and quantify functional capillaries in cremaster muscles. I/R markedly increased the number of rolling, adhering, and migrating leukocytes. It was also observed that I/R significantly increased TNF- expression in these injured tissues. On the other hand, IPC prevented I/R-induced increases in leukocyte rolling, adhesion, and transmigration. Moreover, TNF- protein production and its mRNA expression were downregulated in the IPC group. Finally, I/R-induced IB- phosphorylation and NF-B (p65) nuclear translocation were both suppressed by IPC. These results indicated that IPC attenuated NF-B activation and subsequently reduced TNF- expression, which resulted in the amelioration of microcirculatory disturbances in I/R-injured cremaster muscles. 相似文献
19.
M. K. Banerjee M. K. Kalloo 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1987,73(5):707-710
Summary One hundred and twenty-two varieties, lines and wild accessions of Lycopersicon were screened under three different regimes during the autumn/winter season of 1982–83 and 1983–84 for resistance to tomato leaf curl virus (TLCV). L. hirsutum f. glabratum (B6013) and L. hirsutum f. typicum (A1904) proved to be highly resistant to TLCV in all three environments. Various accessions of L. peruvianum were also highly resistant. L. pimpinellifolium (A1921) exhibited no TLCV symptoms within 90 days. Of the cultivated varieties, Acc 99 exhibited the minimim score for susceptibility; AC 142, Collection No. 2, Kalyanpur Angurlata and HS 101 had a low rating for virus incidence. The inheritance of resistance was studied in the interspecific crosses between a TLCV resistant line of L. pimpinellifolium (A1921) and five (HS 101, HS 102, HS 110, Pusa Ruby and Punjab Chhuhara) susceptible cultivars of L. esculentum. Parents, F1, F2 and backcross progenies were artificially inoculated with local strains of TLCV using vector the viruliferious whitefly, Bemisia tabaci (Genn.). Data indicated that the resistance of L. pimpinellifolium (A 1921) is monogenic and incompletely dominant over susceptibility. 相似文献
20.
Bodrova ME Brailovskaya IV Efron GI Starkov AA Mokhova EN 《Biochemistry. Biokhimii?a》2003,68(4):391-398
At low Ca2+ concentrations the pore of the inner mitochondrial membrane can open in substates with lower permeability (Hunter, D. R., and Haworth, R. A. (1979) Arch. Biochem. Biophys., 195, 468-477). Recently, we showed that Ca2+ loading of mitochondria augments the cyclosporin A-dependent decrease in transmembrane potential () across the inner mitochondrial membrane caused by 10 M myristic acid but does not affect the stimulation of respiration by this fatty acid. We have proposed that in our experiments the pore opened in a substate with lower permeability rather than in the classic state (Bodrova, M. E., et al. (2000) IUBMB Life, 50, 189-194). Here we show that under conditions lowering the probability of classic pore opening in Ca2+-loaded mitochondria myristic acid induces the cyclosporin A-sensitive decrease and mitochondrial swelling more effectively than uncoupler SF6847 does, though their protonophoric activities are equal. In the absence of Pi and presence of succinate and rotenone (with or without glutamate) cyclosporin A either reversed or only stopped decrease induced by 5 M myristic acid and 5 M Ca2+. In the last case nigericin, when added after cyclosporin A, reversed the decrease, and the following addition of EGTA produced only a weak (if any) increase. In Pi-containing medium (in the presence of glutamate and malate) cyclosporin A reversed the decrease. These data show that the cyclosporin A-sensitive decrease in by low concentrations of fatty acids and Ca2+ cannot be explained by specific uncoupling effect of fatty acid. We propose that: 1) low concentrations of Ca2+ and fatty acid induce the pore opening in a substate with a selective cation permeability, and the cyclosporin A-sensitive decrease results from a conversion of to pH gradient due to the electrogenic cation transport in mitochondria; 2) the ADP/ATP-antiporter is involved in this process; 3) higher efficiency of fatty acid compared to SF6847 in the Ca2+-dependent pore opening seems to be due to its interaction with the nucleotide-binding site of the ADP/ATP-antiporter and higher affinity of fatty acids to cations. 相似文献