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71.
Background
Mistic is a unique Bacillus subtilis protein with virtually no detectable homologues in GenBank, which appears to integrate into the bacterial membrane despite an overall hydrophilic composition. These unusual properties have been shown to be useful for high-yield recombinant expression of other membrane proteins through fusion to the C-terminus of Mistic. To better understand the structure and function of Mistic, we systematically searched for and characterized homologous proteins among closely related bacteria. 相似文献72.
Macrozoobenthos of Lake Peipsi-Pihkva: long-term biomass changes 总被引:1,自引:1,他引:0
Macrozoobenthos of the large (3,558 km2) Lake Peipsi-Pihkva was monitored at 22–24 sampling spots yearly in June 1964–1994 as well as 50 shallow-water profiles in mid-summer 1970, 1980, and 1990. No qualitative changes were observed in the bottom fauna, except for the introduction of a Baikalian gammarid species, Gmelinoides fasciatus. The average total biomass in June (without big molluscs) revealed considerable annual fluctuations, with an insignificant general tendency of increase. The increase was significant in the biomass of several Mollusca (including the highly abundant big clam Dreissena polymorpha), Asellus, Gammaridae, and Hirudinea but not in the most abundant animal groups Chironomidae and Oligochaeta. The low biomass of Ephemeroptera and Hydrachnellae decreased significantly. The mid-summer samples taken from the shallow-water zone in three different years revealed the highest biomass in 1980 and the lowest in 1990 (the latter being probably related to the high water level). A gradual decrease in the biomass of the Ephemeroptera and Hydrachnellae as well as the Oligochaeta, Pisidiidae and Bithynia tentaculata occurred in the shallow-water zone, while the Gammaridae increased on the account of the introduced species. No coincidence was found with the neighbouring Lake Võrtsjärv when comparing the annual fluctuations of biomass. A general tendency to a slow increase in total biomass and a decrease in the biomass of the most vulnerable groups Ephemeroptera and Hydrachnellae, probably due to progressing eutrophication, were common for both lakes. 相似文献