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1.
Novel 3-elongated arylalkoxybenzamide derivatives were designed, synthesized and evaluated for their cell division inhibitory activity and antibacterial activity. Among them, the subseries of 3-alkyloxybenzamide derivatives exhibited greatly improved on-target activity against Bacillus subtilis and Staphylococcus aureus, and remarkably increased antibacterial activity against B. subtilis ATCC9372, penicillin-susceptible S. aureus ATCC25923, methicillin-resistant S. aureus ATCC29213 (MRSA) and penicillin-resistant S. aureus PR compared with 3-methoxybenzamide. In contrast, the subseries of 3-phenoxyaklyloxybenzamide, 3-heteroarylalkyloxybenzamide and 3-heteroarylthioalkyloxybenzamide derivatives only showed a significant improvement in on-target activity and antibacterial activity against B. subtilis ATCC9372.  相似文献   

2.
The effects of synergists on the morphogenetic activity of farnesyl methyl ether (a), 10,11-episulphido farnesyl methyl ether (b), 10,11-epoxyfarnesyl methyl ether (c), farnesyl methyl sulphide (d), farnesyl methyl sulphoxide (e) and ethyl 10,11-episulphido farnesoate (f) were determined. Both synergists showed very low juvenilizing activity. All compounds except f were more active in T. molitor. a < b < c showed increasing order of basal activity and of synergism. d had low activity in both insects and was not affected by piperonyl butoxide (PB). In O. fasciatus, e had low activity which was slightly increased by PB. However, in T. molitor e showed moderate activity that was decreased by PB, suggesting an activation reaction, possibly to the sulphone. f showed high activity which was little affected by synergists.  相似文献   

3.
In Arabidopsis thaliana, the process of shoot regeneration in vitro requires the presence of specific miRNAs. We describe here the β-glucuronidase (GUS) expression domains for miR165a/166b, REV, and WUS/CLV3 during direct shoot regeneration. Increased GUS activity of miR166b and REV were first detected within the shoot apical meristem of explants, while no pmiR165a::GUS activity appeared there. The zone of pWUS::GUS activity covered the inner sides of developing protuberances, while that of pCLV3::GUS was more restricted. Once the primary shoot had emerged from the protuberance, pREV::GUS activity was turned on throughout the protuberance. pmiR165a::GUS activity was detected in a small number of protuberance surface cells, while pWUS::GUS activity was restricted to within a few cells beneath the protuberance surface. After the differentiation of leaf-like structures, GUS activity for miR165a and miR166b appeared largely on their abaxial surface, while pWUS::GUS activity was concentrated at the apex of the primary shoot, and no pCLV3::GUS activity was detectable. Following the formation of secondary shoots, pmiR165a::GUS activity was detected on their abaxial surface. GUS activity for miR166b, REV, and WUS/CLV3 were concentrated in the stem apical meristem. The observations suggested that each member of this set of genes might play a distinct role in both primary and secondary shoot regeneration.  相似文献   

4.
Paul G. Kratzer 《Genetics》1983,104(4):685-698
X-chromosome activity in early mouse development has been studied by a gene dosage method that involves measuring the activity level of the X-linked enzyme hypoxanthine phosphoribosyl transferase (HPRT) in single eggs and embryos from XO females and from females heterozygous for In(X)1H, a paracentric inversion of the X chromosome. The HPRT activity in oocytes increased threefold over a 24-hr period beginning after ovulation. Afterward, the activity plateaued in unfertilized eggs but continued to increase for at least 66 hr in presumed OY embryos. Both before and after ovulation, the level of activity in unfertilized eggs from In(X)/X females was twice that from XO females, and the distributions of activity in eggs for both sets of females remained unimodal. Beginning with the two-cell stage, distributions of activity for embryos from In(X)/X females were trimodal, which is evidence for embryonic activity. It is proposed that activation of a maternal mRNA or proenzyme is responsible for the HPRT activity increase in oocytes and early embryos and is supplemented by dosage-dependent activity of the embryonic Hprt gene as early as the two-cell stage.  相似文献   

5.
《Journal of Asia》2014,17(2):169-174
The robber fly, Promachus yesonicus, a predator of scarab adults and larvae was observed on golf clubs in Korea to determine its seasonal activity, daily activity, and relationship to scarab adult activity. P. yesonicus adult density varied more than 10-fold among the four golf clubs where it was observed, with the most activity being at golf clubs with the most scarab adults in June and July. At Yongwon Golf Club P. yesonicus activity closely tracked Popillia quadriguttata activity and both peaked in late June and early July. The ratio of scarab adults (mostly P. quadriguttata):P. yesonicus adults was 8:1. On average mean of 7.5% of all P. yesonicus adults observed in visual surveys were holding captured prey. 50% of all captured prey was a scarab turf pest, P. quadriguttata. At Yongwon Golf Club, regression analysis indicates that P. quadriguttata activity explains 75% of the variation in activity of P. yesonicus. The potential impact of P. yesonicus on populations of P. quadriguttata and other scarab turf pests is discussed.  相似文献   

6.
Phenylalanine ammonia-lyase activity was investigated in preparations representing various parts of sweetclover (Melilotus alba Desr.) plants of CuCu and cucu genotypes. In contrast to other plant parts, very young leaves and stems of CuCu plants displayed high phenylalanine ammonia-lyase activity. Initial leaf samples from CuCu plants were approximately 3 times as high in enzyme activity as leaves from cucu plants, but stems were only slightly higher in activity. Defoliation of the plants resulted in decreased enzyme activity, increased o-hydroxycinnamic acid content, and essentially no difference in enzyme activity between the genotypes. It appears that phenylalanine ammonia-lyase activity in leaves is not primarily controlled by the Cu/cu alleles and that the reaction catalyzed by this enzyme is not the limiting step in o-hydroxycinnamic acid synthesis.  相似文献   

7.
During three last larval instars of Barathra brassicae the alanine aminotransferase activity pattern exhibits two maxima which do not correspond with the maxima of activity of phosphatases and proteases. In the larvae infected by Nosema plodiae a different course of activity can be seen from the 5th day of infection. The activity pattern in the diseased larvae rises above that of a normal larva by 90% shortly before the last molt and reaches a maximum at the end of normal larval development. Alanine aminotransferase in the gut and in the fat body exhibits two main pH optima of activity, 8.0 and 9.5, respectively, and a low activity peak at pH 4.5. This last activity is not present in diseased animals. The temperature and pH inactivation are also described.  相似文献   

8.
9.
The Fab-7 boundary is required to ensure that the iab-6 and iab-7 cis-regulatory domains in the Drosophila Bithorax complex can function autonomously. Though Fab-7 functions as a boundary from early embryogenesis through to the adult stage, this constitutive boundary activity depends on subelements whose activity is developmentally restricted. In the studies reported here, we have identified a factor, called early boundary activity (Elba), that confers Fab-7 boundary activity during early embryogenesis. The Elba factor binds to a recognition sequence within a Fab-7 subelement that has enhancer-blocking activity during early embryogenesis, but not during mid-embryogenesis or in the adult. We found that the Elba factor is present in early embryos but largely disappears during mid-embryogenesis. We show that mutations in the Elba recognition sequence that eliminate Elba binding in nuclear extracts disrupt the early boundary activity of the Fab-7 subelement. Conversely, we find that early boundary activity can be reconstituted by multimerizing the Elba recognition site.  相似文献   

10.
Mucor fragilis grown on bovine blood powder as the sole carbon source abundantly produced β-N-acetylhexosaminidase. The enzyme activity was several times higher than that of a culture obtained with glucose medium. The enzyme had two different molecular weight forms. The high-molecular-weight form had somewhat higher β-N-acetylgalactosaminidase activity than the lower-molecular-weight enzyme which had β-N-acetylgalactosaminidase activity equivalent to about 40% of its β-N-acetylglucosaminidase activity. Bovine blood seemed to induce both enzymes, but N-acetylamino sugars specifically induced the low-molecular-weight form. N-Acetylgalactosamine had an especially marked effect on activity. The low-molecular-weight form of enzyme was purified from the culture filtrate by fractionation with ammonium sulfate and various column chromatographies. The purified enzyme was found to be homogeneous by polyacrylamide gel electrophoresis. The optimum pH was 4.0 to 5.0 for β-N-acetylglucosaminidase activity and 5.5 to 6.5 for β-N-acetylgalactosaminidase activity. The enzyme hydrolyzed natural substrates such as di-N-acetylchitobiose, tri-N-acetylchitotriose, and a glycopeptide obtained by modification of fetuin.  相似文献   

11.
Loss in pancreatic weight and an overall decrease in amylolytic activity in the pancreas were seen in broiler chickens infected with Eimeria acervulina, E. maxima, and E. necatrix. Only E. acervulina and E. maxima reduced amylolytic activity in the surface mucosa of the regions they infected. Surface-bound amylolytic activity decreased as the severity of infection (as measured by lesion score) with E. acervulina increased. This decrease in activity was not related to the decreased feed consumption in infected birds. Little decrease in amylase activity was found in the lumenal contents with the exception of E. acervulina in the jejunum. When the effect of pH on enzyme activity was studied in vitro, a marked reduction in amylolytic activity was observed as the pH went below 5.0.  相似文献   

12.
Lysed chloroplasts from several higher plants synthesized ent-kaurene from copalyl pyrophosphate but not from geranylgeranyl pyrophosphate. The copalyl pyrophosphate transforming activity (so-called B activity of kaurene synthetase) was relatively stable in plastid lysates from Pisum sativum but remarkably unstable in similar preparations of Hordeum vulgare. The bulk of the B activity of kaurene synthetase appeared to reside in the stroma of plastids from P. sativum but required the presence of plastid membranes for maximum activity.  相似文献   

13.
14.
Carbonic anhydrase (CA) activity and localization have been examined in two species of the eukaryotic green alga Chlorella. Mass spectrometric and potentiometric assays of CA activity indicate that C. ellipsoidea contains very little extracellular CA activity whereas C. saccharophila exhibits significant extracellular activity when grown at alkaline pH values. Extracellular CA activity appears to be correlated with the presence of a 36 kilodalton polypeptide that was detected immunologically using a polyclonal antibody directed against the 37 kilodalton Chlamydomonas CA monomer. Both Chlorella species and enzymatically isolated C. ellipsoidea chloroplasts also contain an immunologically similar 38 kilodalton polypeptide that may be a cytosolic or chloroplastic form of CA.  相似文献   

15.
This paper describes a partially heat-labile, naturally occurring bactericidal factor in cell-free hemolymph preparations obtained from Limulus polyphemus. This bactericidal activity has been shown to be directed against two Gram-negative bacteria, Escherichia coli and Klebsiella pneumoniae, whereas it had no effect on the Gram-positive bacteria tested, Micrococcus lysodeikticus and Staphylococcus aureus. Maximal bactericidal activity of this factor was observed at 30°C and pH 6.0. Since complement and antibody are required for antimicrobial activity in vertebrate sera, the activity of this factor in the presence of various complement inhibitors was assayed. The bactericidal activity of Limulus hemolymph is abolished by treatment with endotoxin; however, other anticomplementary substances were without effect. Limulus amebocyte lysate is known to contain protein which may be precipitated by endotoxin; it is possible that the reduction of bactericidal activity produced by endotoxin treatment may be caused by the denaturation of a bactericidal protein moiety produced by the hemocytes.  相似文献   

16.
A series of phenanthroquinolizidine alkaloids 1–24 were prepared and first evaluated for their antiviral activity against tobacco mosaic virus (TMV). The bioassay results showed that most of these compounds exhibited good to excellent in vivo anti-TMV activity, of which compounds 1, 2, 15 and 16 displayed significantly higher activity than (R)-antofine and commercial Ningnanmycin at the same test condition. The substituents on the phenanthrene moiety play an important role for maintaining high in vivo antiviral activity. The introduction of 6-hydroxyl, which is proposed to interact with TMV RNA, did increased anti-TMV activity. The 14aR-configuration was confirmed to be the preferred antiviral configuration for phenanthroquinolizidine alkaloids. Introduction of hydroxy group at 15-position of phenanthroquinolizidine alkaloids increased activity for S-configuration but decreased activity for R-configuration. Present study provides fundamental support for development and optimization of phenanthroquinolizidine alkaloids as potential inhibitors of plant virus.  相似文献   

17.
To evaluate phytochemical constituents from the methanolic extracts of medicinal plants Aloe castellorum and Aloe pseudorubroviolacea. The cytotoxic activity of Aloe castellorum and Aloe pseudorubroviolacea leaf extracts against Human colon cancer cell line (HCT-116) was also assessed. The two medicinal plant extracts having significant cytotoxic activity, meanwhile the methanolic extract of Aloe castellorum shows higher cytotoxic activity than Aloe pseudorubroviolacea extract. The Aloe castellorum shows remarkable activity against respective cell line than control. The characteristic chemical constituents of Aloe castellorum and Aloe pseudorubroviolacea leaf extracts were recognized from Gas chromatography and Mass spectrometry (GC–MS) technique. The molecular docking studies also support the cytotoxic activity.  相似文献   

18.
Many studies of alcohol adaptation in Drosophila melanogaster have focused on the Adh polymorphism, yet the metabolic elimination of alcohol should involve many enzymes and pathways. Here we evaluate the effects of glycerol-3-phosphate dehydrogenase (Gpdh) and cytosolic malate dehydrogenase (Mdh1) genotype activity on adult tolerance to ethanol. We have created a set of P-element-excision-derived Gpdh, Mdh1, and Adh alleles that generate a range of activity phenotypes from full to zero activity. Comparisons of paired Gpdh genotypes possessing 10 and 60% normal activity and 66 and 100% normal activity show significant effects where higher activity increases tolerance. Mdh1 null allele homozygotes show reductions in tolerance. We use piggyBac FLP–FRT site-specific recombination to create deletions and duplications of Gpdh. Duplications show an increase of 50% in activity and an increase of adult tolerance to ethanol exposure. These studies show that the molecular polymorphism associated with GPDH activity could be maintained in natural populations by selection related to adaptation to alcohols. Finally, we examine the interactions between activity genotypes for Gpdh, Mdh1, and Adh. We find no significant interlocus interactions. Observations on Mdh1 in both Gpdh and Adh backgrounds demonstrate significant increases in ethanol tolerance with partial reductions (50%) in cytosolic MDH activity. This observation strongly suggests the operation of pyruvate–malate and, in particular, pyruvate–citrate cycling in adaptation to alcohol exposure. We propose that an understanding of the evolution of tolerance to alcohols will require a system-level approach, rather than a focus on single enzymes.  相似文献   

19.
The adaptiveness of plasticity of digestive enzyme responses to allelochemical stress was tested on 32 full-sib families of gypsy moth larvae from an oak forest population (the Quercus population) and 26 families from a locust-tree forest (the Robinia population), reared either on control diet, or on tannin-supplemented diet. Using the duration of larval development as an indirect measure of fitness, phenotypic selection analyses revealed that lower specific activities of total proteases and trypsin, and higher specific activity of leucine aminopeptidase were adaptive for both populations in the control environment. Plasticity was only shown to be costly for total proteases and trypsin activity in Quercus larvae. In a stressful environment, the most apparent adaptive response was a significant increase in lipase activity. There was no plasticity cost for lipase activity. The two populations differed in the direction of selection acting on α-glucosidase activity, which favoured decreased activity in Quercus larvae and increased activity in Robinia larvae in the control environment. α-glucosidase activity in Quercus larvae is characterized by cost of homeostasis, while cost of plasticity was shown for Robinia larvae. The results obtained on the plasticity of digestive enzyme activity indicate how this generalist species copes with variation in plant allelochemicals.  相似文献   

20.
《Anaerobe》2001,7(5):237-240
Trovafloxacin is a fluoroquinolone antimicrobial with improved in vitro activity against many anaerobic bacteria. We investigated the serum bactericidal activity of trovafloxacin against isolates of Bacteroides fragilis, Bacteroides thetaiotaomicron, Clostridium perfringens, and Peptostreptococcus magnus using a broth microdilution method. All procedures were performed in an anaerobic chamber. A single 200 mg oral dose of trovafloxacin was administered to six healthy volunteers and serum samples were obtained at 0, 2, 4, 6, 8, 10, 12 and 24 h post-dose. Bactericidal activity of these samples demonstrated that at 2 h all samples showed bactericidal activity against all four isolates. Prolonged bactericidal activity (12 to 24 h) was observed against three of the four isolates. Bactericidal activity was not observed after the first sampling period for the B. thetaiotaomicron strain. In this pharmacodynamic model, we found that trovafloxacin provided serum bactericidal activity against several common anaerobic pathogens associated with clinical infections.  相似文献   

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