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21.
ANGELA J. DAVIES 《The Journal of eukaryotic microbiology》1978,25(1):15-21
SYNOPSIS. Examination of littoral fish Blennius pholis and Cottus bubalis caught at Aberystwyth and Porth Cwyfan, Wales. U.K., revealed 2 species of coccidia.
Eimeria dingleyi sp. n. Oocysts spherical (16.1–19.2) to subspherical (13.9–14.2 × 18.8–20.0) μm, with thin walls; sporulation outside the host to produce ellipsoid sporocysts; endogenous phases in epithelial cells throughout intestine; 26 of 58 B. pholis infected.
Eimeria variabilis (Thélohan) Reichenow. Oocysts spherical (11.9–14.6) to subspherical (9.2–10.9 × 13.9–14.3) μm; sporulation in lining of pyloric ceca and rectum; previously unrecorded schizonts and gametocytes present; 21 of 25 C. bubalis infected.
Electron microscopy revealed that the oocyst wall of E. variabilis consists of a thin membrane whereas the sporocyst wall is thick and 3-layered. Typical oocyst wall-forming bodies were absent from the macrogamete. Cytochemical tests on the endogenous stages of E. dingleyi and E. variabilis indicated that in general they resembled other coccidia in their chemical constitution. 相似文献
Eimeria dingleyi sp. n. Oocysts spherical (16.1–19.2) to subspherical (13.9–14.2 × 18.8–20.0) μm, with thin walls; sporulation outside the host to produce ellipsoid sporocysts; endogenous phases in epithelial cells throughout intestine; 26 of 58 B. pholis infected.
Eimeria variabilis (Thélohan) Reichenow. Oocysts spherical (11.9–14.6) to subspherical (9.2–10.9 × 13.9–14.3) μm; sporulation in lining of pyloric ceca and rectum; previously unrecorded schizonts and gametocytes present; 21 of 25 C. bubalis infected.
Electron microscopy revealed that the oocyst wall of E. variabilis consists of a thin membrane whereas the sporocyst wall is thick and 3-layered. Typical oocyst wall-forming bodies were absent from the macrogamete. Cytochemical tests on the endogenous stages of E. dingleyi and E. variabilis indicated that in general they resembled other coccidia in their chemical constitution. 相似文献
22.
SYNOPSIS. A new species of Microsporida, Burenella dimorpha sp. n., representing a new family, Burenellidae fam. n. and genus, is described on the basis of light- and electron-microscope observations. The family is characterized by 2 sequences of sporogony, each sequence having morphologically different sporonts and spores. The parasite infects the tropical fire ant, Solenopsis geminata (Fabricius), producing distinct pathologic manifestations (clearing of the cuticle and eye malformation) and death in the pupal stage of development. Transmission of the infection per os to healthy S. geminata, to the Southern fire ant, Solenopsis xyloni McCook, and to the red and black imported fire ants, Solenopsis invicta Buren and Solenopsis richteri Forel, is reported. 相似文献
23.
Naoya YASHIRO Yoshimi HIROSE Jeffrey Y. HONDA Yoshinori TAKEUCHI Toshihisa YASHIRO 《Entomological Science》2012,15(2):189-196
A new species of Trichogramma that parasitizes Sialis melania eggs is described as Trichogramma tajimaense Yashiro, Hirose and Honda, sp. nov. from Japan. Its phylogenetic position is based on a DNA‐based analysis, and data regarding its male wing polymorphism are also presented. The view that T. tajimaense is closely related to T. semblidis, another parasitoid of Sialis eggs, is supported by the results of a phylogenetic analysis, as well as by the biological and morphological similarities between both species. Trichogramma tajimaense is also similar in male wing polymorphism to T. kurosuae, a gregarious egg parasitoid of the lepidopteran Ivela auripes, as both Trichogramma species exhibit male wing trimorphism (fully alate, brachypterous and apterous forms) in contrast to the male wing dimorphism (fully alate and apterous forms) of T. semblidis. However, no phylogenetic analysis reveals a close relationship between T. tajimaense and T. kurosuae, and a difference exists between these two species in the mean percentage of flightless (brachypterous and apterous) males that emerge from a host egg mass; 96% of T. tajimaense males are incapable of flight, whereas about 50% of T. kurosuae males are flightless. Because all or almost all males of T. semblidis parasitizing Sialis eggs are apterous, T. tajimaense is more similar to T. semblidis than to T. kurosuae in the proportion of flightless males. In addition, male wing polymorphisms of Trichogramma in relation to mating systems could also show a similarity between T. tajimaense and T. semblidis when considering both species as quasi‐gregarious parasitoids of Sialis eggs. 相似文献
24.
G. Kozianowski F. Canganella F. A. Rainey H. Hippe G. Antranikian 《Extremophiles : life under extreme conditions》1997,1(4):171-182
A novel thermophilic spore-forming anaerobic microorganism (strain Ab9) able to grow on citrus pectin and polygalacturonic
acid (pectate) was isolated from a thermal spa in Italy. The newly isolated strain grows optimally at 70°C with a growth rate
of 0.23 h−1 with pectin and 0.12 h−1 with pectate as substrates. Xylan, starch, and glycogen are also utilized as carbon sources and thermoactive xylanolytic
(highest activity at 70°–75°C), amylolytic as well as pullulolytic enzymes (highest activity at 80°–85°C) are formed. Two
thermoactive pectate lyases were isolated from the supernatant of a 300-l culture of isolate Ab9 after growth on citrus pectin.
The two enzymes (lyases a and b) were purified to homogeneity by ammonium sulfate treatment, anion exchange chromatography, hydrophobic chromatography and
finally by preparative gel electrophoresis. After sodium dodecylsulfate (SDS) gel electrophoresis, lyase a appeared as a single polypeptide with a molecular mass of 135 000 Da whereas lyase b consisted of two subunits with molecular masses of 93 000 Da and 158 000 Da. Both enzymes displayed similar catalytic properties
with optimal activity at pH 9.0 and 80°C. The enzymes were very stable at 70°C and at 80°C with a half-life of more than 60
min. The maximal activity of the purified lyases was observed with orange pectate (100%) and pectate-sodium salt (90%), whereas
pectin was attacked to a much lesser extent (50%). The K
m values of both lyases for pectate and citrus pectin were 0.5 g·l−1 and 5.0 g·l−1, respectively. After incubation with polygalacturonic acid, mono-, di-, and tri-galacturonate were detected as final products.
A 2.5-fold increase of activity was obtained when pectate lyases were incubated in the presence of 1 mM Ca2+. The addition of 1 mM ethylenediaminetetraacetic acid (EDTA) resulted in complete inhibition of the enzymes. These heat-stable
enzymes represent the first pectate-lyases isolated and characterized from a thermophilic anaerobic bacterium. On the basis
of the results of the 16S rRNA sequence comparisons and the observed phenotypic differences, we propose strain Ab9 as a new
species of Thermoanaerobacter, namely Thermoanaerobacter italicus sp. nov.
Received: May 25, 1997 / Accepted: June 5, 1997 相似文献
25.
26.
We report the occurrence of a freshwater medusa from a laboratory aquarium in Ranchi, Bihar, India. The consistent emergence of these medussae coincided with sunny days after heavy and prolonged rainfall in the months of August to October. The material showed similarity with Limnocnide indica Annandale and L. nepalensis Dumont but differed in many respects, and is given the status of a distinct species, Limnocnida biharensis n.sp.Author to whom all correspondence should be addressed.Author to whom all correspondence should be addressed. 相似文献
27.
《Bioscience, biotechnology, and biochemistry》2013,77(4):990-992
A new salicy lactone was detected from the unidentified Oulenzia sp. and its chemical structure was elucidated as 7-hydroxyphthalide (7-hydroxy-3 H-isobenzofuran-1-one), based on its GC/MS and GC/FT-IR data and SiO2 column behavior. The compound was synthesized by NaBH4 reduction of 3-hydroxyphthalic anhydride. The GC/MS and GC/FT-IR spectra of the natural compound were consistent with those of the synthetic product. Although the compound is known as a medical material, this is the first example of its presence in nature. 相似文献
28.
《Bioscience, biotechnology, and biochemistry》2013,77(7):1146-1147
Pseudomonas sp. strain ST-200 isolated from a humus soil effectively oxidizes cholesterol dissolved in organic solvents but not that suspended in the growth medium. The organism does not assimilate cholesterol. This organism oxidized a variety of 5α- or 5-ene-sterols dissolved in organic solvent. First, the 3β-OH group was oxidized to a ketone group. The 3α-OH group was scarcely oxidized. Successively, C-6 position of 5-ene-steroids was hydroxylated, and a double bond of 5-ene-steroids was transferred from Δ5 to Δ 4. Then, the 6-OH group was oxidized to a ketone group. Persolvent fermentation with ST-200 would provide an effective, convenient, and stereospecific method to oxidize the C-3 and C-6 positions of steroids. 相似文献
29.
Carol S. Turbek David A. Smith Christopher L. Schardl 《FEMS microbiology letters》1992,94(1-2):187-190
Among the antimicrobial phytoalexins produced by Phaseolus vulgaris (French bean) are the prenylated isoflavonoids kievitone and phaseollidin. Two enzyme activities, kievitone hydratase and phaseollidin hydratase, occur in culture filtrates of the bean pathogen, Fusarium solani f. sp. phaseoli, and catalyse similar hydration reactions on the dimethylallyl moieties of the phytoalexins. The enzymes nearly co-purified during hydroxyapatite chromatography followed by preparative native gel electrophoresis. Eluates from successive slices taken from the native gel were assayed for both activities. Although they were not completely separated in the native gel, the activity profiles indicated that the two activities were distinct. The Km of phaseollidin hydratase for phaseollidin was approximately 7 microM. 相似文献
30.