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1.
A. Španová 《Folia microbiologica》1980,25(4):281-288
Temperature-sensitive (ts) mutations of the G101 phage were isolated after mutagenesis with hydroxylamine. A complementation analysis of 61ts mutants showed that these mutants may be divided into at least 12 complementation groups. Twots mutants probably originated in genes which control lytic functions of the G101 phage. It was shown by three factor crosses
that all of the 12ts mutations tested are localized on that side of the “c” region where the probablecI repressor gene is positioned. Sevents mutations is closely linked to thecI
26 clear marker, three exhibit a closer linkage and two do not exhibit any linkage withcI. All mutations isolated until now can be arrange linearly. According to the present knowledge the preliminary genetic map
of the G101 phage is linear. 相似文献
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H. Štorchová 《Biologia Plantarum》1994,36(3):358-358
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F. Šrámek 《Biologia Plantarum》1999,42(4):582-582
8.
Hana Votavová Vladimír Gut Karel Bláha Jaroslav Šponar 《International journal of biological macromolecules》1982,4(6):341-346
DNA complexes with polypeptides (Lys-Ala-Ala)1)] and (Lys-Ala-Ala)34 have been studied using the methods of thermal melting and circular dichroism. Derivative melting curves of (Lys-Ala-Ala)10 DNA differed substantially from those of (Lys-Ala-Ala)34 prepared either by salt gradient dialysis or by direct mixing. Melting curves of the former complex were unimodal or bimodal with Tm increasing continuously withn input lysin-to-DNA phosphate ratio (r); those of the latter complex consisted of three separate transitions with Tm values almost independent of r. Complete reversibility of binding in the (Lys-Ala-Ala)10-DNA system but a slow redistribution of (Lys-Ala-Ala)34 on DNA at low temperature were found in the redistribution experiments Much faster redistribution from denatured to native DNA occurs at the temperature of melting, contributing to the unusual trimodal melting pattern. Circular dichroism curves are very similar for both complexes and indicate little change of DNA conformation upon polypeptide binding. 相似文献
9.
Vital staining of mitochondria with a fluorescent dye 3,3′-diethyloxacarbocyanine was used to follow cell lineage in embryos of Phallusia mammillata. The results agree in general with the plan established by Conklin in 1905. Strong fluorescence migrated after fertilization similarly to the pigment of the “yellow crescent” in Styela. Later, fluorescence segregated into muscle cell primordia, but not into mesenchyme cells. An animal hemisphere cell, b 8.17 also exhibited strong fluorescence and joined a group of muscle primordia, very likely becoming a muscle cell itself. In the tadpole, all the tail muscle cells were fluorescent. Fluorescence was also noticed in nerve cell primordia of the vegetal hemisphere, particularly in the cell A 8.16 whose descendants appeared to become part of the sensory vesicle which was strongly fluorescent in the tadpole. The usefulness of this type of vital staining in following cell lineage of colorless embryos is stressed. 相似文献
10.
Twelve metronidazole-resistant and twelve metronidazole-susceptible strains ofTrichomonas vaginalis were tested for the presence of dsRNA. Three resistant and five susceptible strains were found to contain dsRNA which indicated
that metronidazole resistance does not correlate with the absence of dsRNA. Electron microscopy showed the homogenates of
all dsRNA -positive strains to contain virus-like particles 32 –38 nm in diameter, while no such particles were found in the
dsRNA-negative strains. A mutual relationship between the dsRNA and virus-like particles seems to exist.
After this paper had been accepted for publication the occurrence of virus-like particles in dsRNA-positive trichomonads was
reported by others (Wang A.L., Wang C.C.: The double stranded RNA inTrichomonas vaginalis may originate from virus-like particles.Proc. Nat. Acad. Sci. USA
83, 7956–7961, 1986). 相似文献