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561.
Theresa Dutschei Irena Beidler Daniel Bartosik Julia-Maria Seeßelberg Michelle Teune Marcus Bäumgen Soraia Querido Ferreira Julia Heldmann Felix Nagel Joris Krull Leona Berndt Karen Methling Martin Hein Dörte Becher Peter Langer Mihaela Delcea Michael Lalk Michael Lammers Matthias Höhne Jan-Hendrik Hehemann Thomas Schweder Uwe T. Bornscheuer 《Environmental microbiology》2023,25(9):1713-1727
Marine Bacteroidetes that degrade polysaccharides contribute to carbon cycling in the ocean. Organic matter, including glycans from terrestrial plants, might enter the oceans through rivers. Whether marine bacteria degrade structurally related glycans from diverse sources including terrestrial plants and marine algae was previously unknown. We show that the marine bacterium Flavimarina sp. Hel_I_48 encodes two polysaccharide utilization loci (PULs) which degrade xylans from terrestrial plants and marine algae. Biochemical experiments revealed activity and specificity of the encoded xylanases and associated enzymes of these PULs. Proteomics indicated that these genomic regions respond to glucuronoxylans and arabinoxylans. Substrate specificities of key enzymes suggest dedicated metabolic pathways for xylan utilization. Some of the xylanases were active on different xylans with the conserved β-1,4-linked xylose main chain. Enzyme activity was consistent with growth curves showing Flavimarina sp. Hel_I_48 uses structurally different xylans. The observed abundance of related xylan-degrading enzyme repertoires in genomes of other marine Bacteroidetes indicates similar activities are common in the ocean. The here presented data show that certain marine bacteria are genetically and biochemically variable enough to access parts of structurally diverse xylans from terrestrial plants as well as from marine algal sources. 相似文献
562.
The codon composition of the coding sequence''s (ORF) 5′ end first few dozen codons is known to be distinct to that of the rest of the ORF. Various explanations for the unusual codon distribution in this region have been proposed in recent years, and include, among others, novel regulatory mechanisms of translation initiation and elongation. However, due to the fact that many overlapping regulatory signals are suggested to be associated with this relatively short region, its research is challenging. Here, we review the currently known signals that appear in this region, the theories related to the way they regulate translation and affect the organismal fitness, and the debates they provoke. 相似文献
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565.
H Berndt 《Hoppe-Seyler's Zeitschrift für physiologische Chemie》1979,360(6):765-772
The synthesis of the sequence 71-86 (XIII) of human proinsulin (sequence 6-21 of human insulin-A-chain) via the fragments 71-78 (XIy1,3) and 79-86 (XII) is described. The good solubility of the protected peptide derivatives belonging to the sequences 75-78 (IXx1,2), 79-86 (X), and 71-78 (XIy1,2), and of the fragment 71-86 (XIII) itself in organic solvents allows a quick and efficient purification of these derivatives by liquid chromatography on silica-gel columns. 相似文献
566.
H Berndt H G Gattner H Zahn 《Hoppe-Seyler's Zeitschrift für physiologische Chemie》1975,356(9):1469-1472
The synthetic Des-1-glycine-A-chain of sheep insulin as the monomeric cyclic bisdisulfide and native bovine B-chain bissulfonate were reduced together with mercaptoethanol. They combined at pH 10.6 to yield Des-A1-glycine-insulin. This was purified by gel and ion exchange chromatography. The low insulin activity (0.4 - 0.6%) as measured by the fat cell test as well as the change in the CD spectrum indicated that the loss of the N-terminal glycine of the A-chain results in fully inactive insulin. This confirms the results obtained earlier by partial synthesis of Des-A1-glycine-insulin. 相似文献
567.
Ewa Dubas Gabriela Golebiowska Iwona Zur Maria Wedzony 《Acta Physiologiae Plantarum》2011,33(2):529-537
According to regular reports, one of the most serious diseases of winter cereal and grass varieties in moderate and cold climatic
areas is pink snow mould caused by Microdochium nivale. Currently, the resistance of the economically important cereal species as triticale is not satisfactory. Moreover, there
is no efficient strategy of protection against this pathogen and the understanding of plant resistance mechanisms is rather
poor. Presented paper for the first time shows the cytological analysis of M. nivale infection in model triticale varieties by the use of fluorescent and light microscopy in combination with fluorescent dyes
and hydrogen peroxide staining. Both, the infection level and the dynamic of the process varied for tested genotypes confirming
the field and laboratory data of their different resistance to this pathogen. Moreover, our analysis showed that in both cultivars
cold-hardening of seedlings delayed the mycelium growth. In both cultivars, hyphal walls and fungal penetration sites were
visualized in crowns, leaf sheaths and leaves of hardened and non-hardened inoculated seedlings. For the first time the presence
of the haustoria produced by M. nivale was confirmed in those tissues. Single infection hyphae usually penetrated into the host tissues via stomatal apparatuses
were accompanied by the efflux of hydrogen peroxide. The data show a great potential of fluorescence techniques in studying
the host plant–pathogen interactions providing a better insight into plant defence reactions that may allow elaboration of
the efficient breeding strategies aimed at increasing resistance to this pathogenic fungus. 相似文献
568.
Reinhard Berndt 《Mycological Progress》2005,4(4):339-341
Phakopsora allophyli (Basidiomycota, Uredinales) is described on the basis of the type specimen of Uredo allophili Henn. on Allophylus sp. (Sapindaceae) from Tanzania. The species has paraphysate telia and teliospores with a single papillate germ pore. These
features are unusual for members of the genus Phakopsora. The generic affiliation of the fungus with Phakopsora is discussed. 相似文献
569.
570.
Crosslinking of protein molecules with bifunctional reagents and subsequent electrophoresis of the modified proteins revealed the presence of cytochrome P-450 LM 2 oligomers in proteoliposome membranes obtained in different ways and differing in their phospholipid composition. Data from a comparative analysis of cytochrome P-450 oligomeric structures in solution and in membrane are suggestive of the hexameric organization of cytochrome P-450 LM 2 within proteoliposome membranes. 相似文献