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1.
ADP-ribosyltransferase activity of pertussis toxin and immunomodulation by Bordetella pertussis 总被引：22，自引：0，他引：22
W J Black J J Munoz M G Peacock P A Schad J L Cowell J J Burchall M Lim A Kent L Steinman S Falkow 《Science (New York, N.Y.)》1988,240(4852):656-659
Pertussis toxin is produced by the causative agent of whooping cough, Bordetella pertussis, and is an adenosine diphosphate (ADP)-ribosyltransferase capable of covalently modifying and thereby inactivating many eukaryotic G proteins involved in cellular metabolism. The toxin is a principal determinant of virulence in whooping cough and is a primary candidate for an acellular pertussis vaccine, yet it is unclear whether the ADP-ribosyltransferase activity is required for both pathogenic and immunoprotective activities. A B. pertussis strain that produced an assembled pertussis holotoxin with only 1 percent of the ADP-ribosyltransferase activity of the native toxin was constructed and was found to be deficient in pathogenic activities associated with B. pertussis including induction of leukocytosis, potentiation of anaphylaxis, and stimulation of histamine sensitivity. Moreover, this mutant strain failed to function as an adjuvant and was less effective in protecting mice from intracerebral challenge infection. These data suggest that the ADP-ribosyltransferase activity is necessary for both pathogenicity and optimum immunoprotection. These findings bear directly on the design of a nontoxic pertussis vaccine. 相似文献
2.
Pertussis toxin gene: nucleotide sequence and genetic organization 总被引：104，自引：0，他引：104
The current pertussis vaccines, although efficacious, in some instances produce undesirable side effects. Molecular engineering of pertussis toxin, the major protective antigen, could provide a safer, new generation of vaccines against whooping cough. As a first critical step in the development of such a vaccine, the complete nucleotide sequence of the pertussis toxin gene was determined and the amino acid sequences of the individual subunits were deduced. All five subunits are coded by closely linked cistrons. A promoter-like structure was found in the 5'-flanking region, suggesting that the toxin is expressed through a polycistronic messenger RNA. The order of the cistrons is S1, S2, S4, S5, and S3. All subunits contain signal peptides of variable length. The calculated molecular weights of the mature subunits are 26,024 for S1, 21,924 for S2, 21,873 for S3, 12,058 for S4, and 11,013 for S5. Subunits S2 and S3 share 70% amino acid homology and 75% nucleotide homology. Subunit S1 contains two regions of eight amino acids homologous to analogous regions in the A subunit of both cholera and Escherichia coli heat labile toxins. 相似文献
3.
Pertussis toxin S1 mutant with reduced enzyme activity and a conserved protective epitope 总被引：28，自引：0，他引：28
W N Burnette W Cieplak V L Mar K T Kaljot H Sato J M Keith 《Science (New York, N.Y.)》1988,242(4875):72-74
Pertussis toxin (PTX) is a major virulence factor in whooping cough and can elicit protective antibodies. Amino acid residues 8 to 15 of PTX subunit S1 are important for the adenosine diphosphate-ribosyltransferase activity associated with the pathobiological effects of PTX. Furthermore, this region contains at least a portion of an epitope that elicits both toxin-neutralizing and protective antibody responses in mice. The gene encoding the S1 subunit was subjected to site-specific mutagenesis in this critical region. A mutant containing a single amino acid substitution (Arg9----Lys) had reduced enzymatic activity (approximately 0.02% of control) while retaining the protective epitope. This analog S1 molecule may provide the basis for a genetically detoxified PTX with potential for use as a component of an acellular vaccine against whooping cough. 相似文献
4.
Pertussis toxin-sensitive pathway in the stimulation of c-myc expression and DNA synthesis by bombesin 总被引：20，自引：0，他引：20
The bombesin-like peptides are potent mitogens for Swiss 3T3 fibroblasts, human bronchial epithelial cells, and cells isolated from small cell carcinoma of the lung. The mechanism of signal transduction in the proliferative response to bombesin was investigated by studying the effect of Bordetella pertussis toxin on bombesin-stimulated mitogenesis. At nanomolar concentrations, bombesin increased levels of c-myc messenger RNA and stimulated DNA synthesis in Swiss 3T3 cells. Treatment of the cells with pertussis toxin (5 nanograms per milliliter) completely blocked bombesin-enhanced c-myc expression and eliminated bombesin-stimulated DNA synthesis. This treatment had essentially no effect on the mitogenic responses to either platelet-derived growth factor or phorbol 12,13-dibutyrate. These results suggest that the mitogenic actions of bombesin-like growth factors are mediated through a pertussis toxin-sensitive guanine nucleotide-binding protein. Furthermore they indicate that bombesin-like growth factors act through pathways that are different from those activated by platelet-derived growth factor. 相似文献
5.
The epidemiology of whooping cough (pertussis) remains enigmatic. A leading cause of infant mortality globally, its resurgence in several developed nations--despite the availability and use of vaccines for many decades--has caused alarm. We combined data from a singular natural experiment and a detailed contact network study to show that age-specific contact patterns alone can explain shifts in prevalence and age-stratified incidence in the vaccine era. The practical implications of our results are notable: Ignoring age-structured contacts is likely to result in misinterpretation of epidemiological data and potentially costly policy missteps. 相似文献
6.
Ma RZ Gao J Meeker ND Fillmore PD Tung KS Watanabe T Zachary JF Offner H Blankenhorn EP Teuscher C 《Science (New York, N.Y.)》2002,297(5581):620-623
Bphs controls Bordetella pertussis toxin (PTX)-induced vasoactive amine sensitization elicited by histamine (VAASH) and has an established role in autoimmunity. We report that congenic mapping links Bphs to the histamine H1 receptor gene (Hrh1/H1R) and that H1R differs at three amino acid residues in VAASH-susceptible and -resistant mice. Hrh1-/- mice are protected from VAASH, which can be restored by genetic complementation with a susceptible Bphs/Hrh1 allele, and experimental allergic encephalomyelitis and autoimmune orchitis due to immune deviation. Thus, natural alleles of Hrh1 control both the autoimmune T cell and vascular responses regulated by histamine after PTX sensitization. 相似文献
7.
Phagocyte impotence caused by an invasive bacterial adenylate cyclase 总被引：69，自引：0，他引：69
For unknown reasons, humans infected with the bacterium Bordetella pertussis are exceptionally vulnerable to secondary infections. Bordetella species elaborate a soluble, heat-stable, and highly active adenylate cyclase. This enzyme is internalized by phagocytic cells and catalyzes the unregulated formation of adenosine 3',5'-monophosphate (cyclic AMP), thereby disrupting normal cellular function. This unusual phenomenon may explain Bordetella-induced aphylaxis and may prove to be useful for investigating a variety of cyclic AMP-governed processes. 相似文献
8.
Koropatnick TA Engle JT Apicella MA Stabb EV Goldman WE McFall-Ngai MJ 《Science (New York, N.Y.)》2004,306(5699):1186-1188
Tracheal cytotoxin (TCT), a fragment of the bacterial surface molecule peptidoglycan (PGN), is the factor responsible for the extensive tissue damage characteristic of whooping cough and gonorrhea infections. Here, we report that Vibrio fischeri also releases TCT, which acts in synergy with lipopolysaccharide (LPS) to trigger tissue development in its mutualistic symbiosis with the squid Euprymna scolopes. As components of PGN and LPS have commonly been linked with pathogenesis in animals, these findings demonstrate that host interpretation of these bacterial signal molecules is context dependent. Therefore, such differences in interpretation can lead to either inflammation and disease or to the establishment of a mutually beneficial animal-microbe association. 相似文献
9.
Sequence of the alpha subunit of photoreceptor G protein: homologies between transducin, ras, and elongation factors 总被引：40，自引：0，他引：40
A bovine retinal complementary DNA clone encoding the alpha subunit of transducin (T alpha) was isolated with the use of synthetic oligodeoxynucleotides as probes, and the complete nucleotide sequence of the insert was determined. THe predicted protein sequence of 354 amino acids includes the known sequences of four tryptic peptides and sequences adjacent to the residues that undergo adenosine diphosphate ribosylation by cholera toxin and pertussis toxin. On the basis of homologies to other proteins, such as the elongation factors of protein synthesis and the ras oncogene proteins, regions are identified that are predicted to be acylated and involved in guanine nucleotide binding and hydrolysis. Amino acid sequence similarity between T alpha and ras is confined to these regions of the molecules. 相似文献
10.
Clantin B Delattre AS Rucktooa P Saint N Méli AC Locht C Jacob-Dubuisson F Villeret V 《Science (New York, N.Y.)》2007,317(5840):957-961
In Gram-negative bacteria and eukaryotic organelles, beta-barrel proteins of the outer membrane protein 85-two-partner secretion B (Omp85-TpsB) superfamily are essential components of protein transport machineries. The TpsB transporter FhaC mediates the secretion of Bordetella pertussis filamentous hemagglutinin (FHA). We report the 3.15 A crystal structure of FhaC. The transporter comprises a 16-stranded beta barrel that is occluded by an N-terminal alpha helix and an extracellular loop and a periplasmic module composed of two aligned polypeptide-transport-associated (POTRA) domains. Functional data reveal that FHA binds to the POTRA 1 domain via its N-terminal domain and likely translocates the adhesin-repeated motifs in an extended hairpin conformation, with folding occurring at the cell surface. General features of the mechanism obtained here are likely to apply throughout the superfamily. 相似文献
11.
棉花黄萎病菌分泌的糖蛋白毒素与其致病力的关系 总被引：12，自引：1，他引：12
从4个不同致病力类型棉花黄萎病菌的培养液中提取了致萎毒素，经琼脂糖电泳后扫描显示，各菌系的粗毒素均含有糖蛋白条带2，落叶型菌系糖蛋白条带2的糖基化程度明显高于非落叶型菌系。弱致病力菌系毒素中缺少糖蛋白条带1。经亲和层析法从4个菌系中分别纯化而得的糖蛋白毒素中，落叶型菌系的糖蛋白毒素与亲和载体的亲和力小于非落叶型菌系，表明不同致病类型菌系分泌的糖蛋白毒素中存在糖基组成差异。各菌系中糖蛋白毒素的含量与病菌引起的棉花病情指数呈显著正相关（r=0.9583,P＜0.05）。生物鉴定表明，强致病力菌系糖蛋白毒素的致萎活力明显高于弱致病力菌系。从而认为，病菌致病力不仅与糖蛋白毒素的含量有关，而且也与糖蛋白毒素的化学组成差异有关。 相似文献
12.
Acquisition by innervated cardiac myocytes of a pertussis toxin-specific regulatory protein linked to the alpha 1-receptor 总被引：4，自引：0，他引：4
S F Steinberg E D Drugge J P Bilezikian R B Robinson 《Science (New York, N.Y.)》1985,230(4722):186-188
During development, the chronotropic response of rat ventricular myocardium to alpha 1-adrenergic stimulation changes from positive to negative. The alpha 1-agonist phenylephrine increases the rate of contraction of neonatal rat myocytes cultured alone but decreases the rate of contraction when the myocytes are cultured with functional sympathetic neurons. The developmental induction of the inhibitory myocardial response to alpha 1-adrenergic stimulation in intact ventricle and in cultured myocytes was shown to coincide with the functional acquisition of a substrate for pertussis toxin. A 41-kilodalton protein from myocytes cultured with sympathetic neurons and from adult rat myocardium showed, respectively, 2.2- and 16-fold increases in pertussis toxin-associated ADP-ribosylation (ADP, adenosine diphosphate) as compared to controls. In nerve-muscle cultures, inhibition of the actions of this protein by pertussis toxin-specific ADP-ribosylation reversed the mature inhibitory alpha 1-adrenergic response to an immature stimulatory pattern. The results suggest that innervation is associated with the appearance of a functional pertussis toxin substrate by which the alpha 1-adrenergic response becomes linked to a decrease in automaticity. 相似文献
13.
稻瘟菌粗毒素对水稻幼苗生理生化的影响 总被引：1，自引：0，他引：1
为了检验不同稻瘟菌株粗毒素对杂交水稻生理影响的差异,以稻瘟菌XP、MY菌株不同浓度的粗毒素浸根处理水稻冈优725和B优827的幼苗,并对其防御酶POD和可溶性蛋白进行分析比较。结果表明:稻瘟菌2个菌株的不同毒素浓度均对水稻幼苗的POD活性和可溶性蛋白含量有明显影响,POD均表现出先升高后降低的变化规律;高浓度的毒素处理后,2个水稻品种的可溶性蛋白含量随时间的推移明显降低,但是B优827的可溶性蛋白含量明显高于冈优725,其POD变化与冈优725相比较平缓;B优827对稻瘟菌粗毒素的耐受力强于冈优725。 相似文献
14.
Murine lymphoma: augmented growth in mice with pertussis vaccine-induced lymphocytosis 总被引：3，自引：0，他引：3
Injection of Bordetella pertussis vaccine caused an excessive lymphocytosis, associated with an augmented growth of a lymphoma cell homotransplant in mice. A markedly impaired reactive cell proliferation was revealed in the spleens of the vaccine-pretreated mice after stimulation with phytohemagglutinin or Freund's complete adjuvant. 相似文献
15.
采用室内培养方法,从吴江市郊长期被多环芳烃污染的土壤中富集到以菲为唯一碳源和能源的菲降解复合微生物菌群,复合菌群在7d内对无机盐液体中菲(含量100mg·L-1)的降解率达到99%。从复合菌群中分离纯化获得两株菲高效降解菌B1和L2,经过菌体形态特征、生理生化特征和16SrDNA序列分析,鉴定菌株B1为百日咳博行特氏菌(Bordetella petrii),菌株L2为墨西哥假黄单胞菌(Pseudoxanthomonas mexicana)。这两株菌在菲含量为100mg·L-1的无机盐培养液中,7d内对菲(含量100mg·L-1)的降解率大约为80%,9d内的降解率可达到99%。将复合菌群和菲污染土壤混合,在光照培养箱中进行培养修复。结果表明,修复88d后,接种复合菌群的低污染浓度(8.22mg·kg-1)处理和高污染浓度(39.65mg·kg-1)处理的菲去除率分别达到95.74%和98.06%。 相似文献
16.
A G protein couples serotonin and GABAB receptors to the same channels in hippocampus 总被引：40，自引：0，他引：40
Both serotonin and the selective gamma-aminobutyric acidB (GABAB) agonist, baclofen, increase potassium (K+) conductance in hippocampal pyramidal cells. Although these agonists act on separate receptors, the potassium currents evoked by the agonists are not additive, indicating that the two receptors share the same potassium channels. Experiments with hydrolysis-resistant guanosine triphosphate (GTP) and guanosine diphosphate analogs and pertussis toxin indicate that the opening of the potassium channels by serotonin and GABAB receptors involves a pertussis toxin-sensitive GTP-binding (G) protein, which may directly couple the two receptors to the potassium channel. 相似文献
17.
蜡蚧轮枝菌高产毒素菌株的筛选 总被引：2，自引：1，他引：2
通过比较6株蜡蚧轮枝菌(V3450、Vp28、V l6063、V0175、V342和V341)对烟粉虱3龄若虫的毒力和6株菌株代谢浓缩液对烟粉虱1龄若虫的忌避作用和毒杀作用,筛选出高产毒素菌株.结果表明:6株蜡蚧轮枝菌的LC50分别为2.57×105、6.03×105、6.03×105、1.70×106、7.41×106、1.66×107孢子.mL-1,表明菌株V3450、Vp28、V l6063的毒力比另外3株高;6株菌株代谢浓缩液对烟粉虱1龄若虫的忌避率分别为76.40%、78.22%、73.54%、52.7%、40.80%、53.33%,死亡率分别为80.27%、71.90%、66.66%、50.86%、40.57%、46.67%,表明菌株V3450、Vp28、V l6063的产毒能力比另外3株强,由此筛选出V3450、Vp28、V l6063为高产毒素菌株. 相似文献
18.
从 2～ 3月龄病死獭兔的肺病变组织中分离到 3株细菌 ,经形态特征、培养及生化特性、药敏试验和动物实验等表明 ,分离菌株为能运动、无芽孢的革兰氏阴性小杆菌 ,即支气管败血波氏杆菌。该菌在鲜血平板上产生溶血 ,在麦康凯平板上形成光滑、中央突起的珍珠状菌落 ,且能与兔支气管败血波氏杆菌参考株S80 10 3抗血清发生凝集 ,人工接种小白鼠能引起死亡 ,并从病死鼠中回收到相应细菌 相似文献
19.
方永祥 《甘肃农业大学学报》1986,(1)
本文从两头布病阳性奶牛的产后绒毛膜上所获得两株细菌,进行了鉴定。两株细菌是同一类革兰氏阴性的小杆菌,均具有活泼的运动性;为一端丛毛;与布氏杆菌和支气管败血波氏杆菌有强烈的交又抗原成份,但不是这两个菌种.其许多活性还与产碱杆菌属极为相似。两株获得菌种对小白鼠具有病原性,在临床上能够使动物呈现持续性布氏杆菌病假阳性反应。 相似文献
20.
研究将百日咳杆菌用B-G培养基活化后再在改良的S-S培养基上液体培养,用CTAB-NaCl法提取百日咳杆菌的基因组DNA.经PCR扩增出胰岛激活蛋白 B聚体的四个亚基基因,分别将其克隆于pGEX-6p-1载体上,并探讨了在大肠杆菌BL21(DE3)中可溶性表达IAP B聚体各亚基的可能性.通过控制诱导表达温度,S2,S3均可以实现可溶表达,以GST亲和层析得到的S2终产物0.4 mg/L培养物, S3为0.6 mg/L培养物.S4表达虽是可溶性的,但由于融合蛋白的等电点近于7,多步纯化易损失.S5的表达量太低,有待进一步分析. 相似文献