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21.
Cecilia Gotor Eloísa Pajuelo Luís C. Romero Antonio J. Márquez José M. Vega 《Archives of microbiology》1990,153(3):230-234
Polyclonal antiserum specific for ferredoxin-nitrite reductase (EC 1.7.7.1) from the green alga Chlamydomonas reinhardii recognized the nitrite reductase from other green algae, but did not cross-react with the corresponding enzyme from different cyanobacteria or higher plant leaves. An analogous situation was also found for ferredoxin-glutamate synthase (EC 1.4.7.1), using its specific antiserum. Besides, the antibodies raised against C. reinhardii ferredoxin-glutamate synthase were able to inactivate the ferredoxin-dependent activity of nitrite reductase from green algae.These results suggest that there exist similar domains in ferredoxin-nitrite reductases and ferredoxin-glutamate synthases from green algae. In addition, both types of enzymes share common antigenic determinants, probably located at the ferredoxin-binding domain. In spite of their physicochemical resemblances, no apparent antigenic correlation exists between the corresponding enzymes from green algae and those from higher plant leaves or cyanobacteria.Abbreviations Fd
ferredoxin
- GOGAT
glutamate synthase
- MV+
reduced methyl viologen (radical cation)
- NiR
nitrite reductase
- PMSF
phenylmethylsulphonyl fluoride
- SDS
sodium dodecyl sulfate 相似文献
22.
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24.
N. Romero C. Marsac M. Fardeau M. Droste B. Schneyder B. Kadenbach 《Histochemistry and cell biology》1990,94(2):211-215
Summary The immunohistochemical reaction of monoclonal as well as polyclonal antibodies against cytochrome c oxidase (COX) subunits
with serial sections of normal human skeletal muscle was investigated. The stronger reactivity of polyclonal antibodies to
COX subunits II–III and VIIbc with type I as compared to type II fibres, correlated well with the higher histochemical reactivity
of NADH dehydrogenase, succinate dehydrogenase and cytochrome c oxidase in type I fibres. In contrast an almost exclusive
reaction of a monoclonal antibody against subunit IV with type I fibre and a preponderan reaction of a polyclonal antibody
against subunits Vab with type II fibres was obtained. Antibodies against subuntis I, Vb and VIc did not reveal a fibre-type-specific
reactivity. The data indicate in human muscle the occurrence of fibre type-specific isozymes of cytochrome c oxidase differing
in subunits IV and Va or Vb. 相似文献
25.
Prostaglandin biosynthesis by human decidual cells: effects of inflammatory mediators 总被引:4,自引:0,他引:4
M D Mitchell S Edwin R J Romero 《Prostaglandins, leukotrienes, and essential fatty acids》1990,41(1):35-38
There is substantial evidence that decidual activation, in association with infection, is linked with the onset of both preterm and term labor. We therefore undertook the present study to evaluate prostaglandin production and its potential regulation by inflammatory mediators in human decidual cells in primary monolayer culture. Upon attaining confluence, the cells were incubated with endotoxin, interleukin 1 alpha (IL1 alpha), interleukin 1 beta (IL1 beta); or tumor necrosis factor (TNF). Production of prostaglandin (PG) E2 and PGF2 alpha was determined using specific radioimmunoassays. Endotoxin and these cytokines all induced significant concentration-dependent increases in PGE2 and PGF2 alpha production. Our results suggest that term human decidual cells are responsive to endotoxin and cytokines and that generation of these substances in the decidua or nearby (eg. in response to infection) will lead to increased prostaglandin production and uterine contractions. 相似文献
26.
Daniele Arobba Andrea Quaglia Paolo Panagia Paolo Minuti Sergio Innocenti Pier Luigi Odda 《Aerobiologia》1988,4(1-2):38-46
Riassunto Sono state rilevate durante un monitoraggio aerobiologico effettuato a Pietra Ligure (Savona) nel corso del 1987 le concentrazioni
polliniche di 50 taxa ed è stata valutata l'influenza relativa dei fattori meteorologici. Le osservazioni palinologiche sono
state rapportate alle concentrazioni sieriche delle IgE specifiche, alla reattività bronchiale specifica ed aspecifica valutate
in 101 pazienti allergici (rinitici ed asmatici), sensibilizzati a Graminaceae ed Urticaceae (Parietaria) al fine di riconoscere
correlazioni tra le caratteristiche aerobiologiche di questi allergeni edi meccanismi patogenetici che sostengono la reattività
bronchiale.
相似文献
27.
Announcement
1988 Gordon Conference on Theoretical Biology and Biomathematics Tilton Academy, Tilton, New Hampshire, U.S.A., 13–17 June 1988 相似文献28.
Romero Jorge Liras Paloma Martín Juan F. 《Applied microbiology and biotechnology》1988,27(5-6):510-516
Summary Seven mutants of Streptomyces clavuligerus blocked in the biosynthesis of clavulanic acid, cephamycin C, or both antibiotics, have been isolated and characterized. Mutants nca1 and nca2 were unable to synthesize clavulanic acid but produced cephamycin C. Mutants nce1 and nce2 were completely blocked in cephamycin C production but formed clavulanic acid. A third group (mutants ncc1, ncc4 and ncc5) failed to produce both antibiotics. Arginase activity (forming ornithine) was very low in mutants ncc1 and ncc5. All the mutants blocked in clavulanic acid biosynthesis showed a normal ornithine--aminotransferase activity. Mutant ncc1, blocked in cephamycin biosynthesis, lacked completely lysine--aminotransferase (forming -aminoadipic acid) and isopenicillin N synthase. Two other mutants (nce2 and nce5) lacked isopenicillin N synthase. There was a good correlation between the isopenicillin N synthase and the lysine--aminotransferase activities of the nca mutants and the ability of those strains to produce cephamycin C. The condensing enzyme involved in the formation of the clavulanic acid nucleus appears to be different from the isopenicillin N synthase.Dedicated to Professor H.-J. Rehm on the occasion of his 60th birthday 相似文献
29.
C Junquera M J Azanza P Parra M T Peg J Aisa L M Romero P Garín 《Histology and histopathology》1988,3(2):115-124
The innervation of Rana ridibunda esophagus myenteric plexuses has been studied by the following methods: demonstration of cholinesterase activity; FIF method for catecholamines; immunohistochemistry for VIP, SP and SOM, and conventional electron microscopy. The cholinergic innervation is important in the esophagus wall where, in addition to the well known extrinsic component, there is a rich intrinsic plexus with cells and fibres widely distributed. The esophagus, together with the intestine, are the Rana gut portions where the adrenergic component is more broadly expressed. The adrenergic innervation seems to be almost entirely of extrinsic origin. We have shown that, for the tested peptides, there is an intrinsic innervation represented by VIP, SP and SOM like plexuses. We do not discard nonetheless an extrinsic component. The ultrastructure reveals the morphological characteristics of the enteric neurons as well as the fine inter-relationships between the nervous elements and the functional components of the esophagic wall. 相似文献
30.
Summary A systematic study was made of the action of 4-acetamido-4-isothiocyanostilbene-2,2-disulfonic acid (SITS) and 4,4-diisothiocyanostilbene-2,2-disulfonic acid (DIDS) on active Ca2+ transport of human erythrocytes. Pumping activity was estimated in inside-out vesicles (IOV's) by means of Ca2+-selective electrodes or use of tracer45Ca2+. The stilbenes exhibited an approximately equal inhibitory potency and their action could be overcome by carbonyl cyanidep-trifluoromethoxyphenylhydrazone (FCCP) at low but not at high stilbene concentrations. In the absence of DIDS. Ca2+ transport was not affected upon addition of valinomycin, but it was appreciably reduced when vesicles were preincubated with low DIDS concentrations. Such an effect was strictly dependent on the external K+ concentration and it was abolished when valinomycin was added together with FCCP. Similar results were obtained using IOV's prepared from intact cells which had been previously exposed to the stilbene. The findings clearly demonstrate the presence in human red cells of a partially electrogenic Ca2+ pump, exchanging one Ca2+ ion for one proton. 相似文献