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Isolation and identification of granule-associated proteins relevant for poly(3-hydroxyalkanoic acid) biosynthesis in Chromatium vinosum D 总被引:1,自引:0,他引:1
Matthias Liebergesell Bernhard Schmidt Alexander Steinbüchel 《FEMS microbiology letters》1992,99(2-3):227-232
Abstract Poly(3-hydroxybutyric acid) granules, which harbored only four major granule-associated proteins as revealed by SDS polyacrylamide gel electrophoresis, were isolated from crude cellular extracts of Chromatium vinosum D by centrifugation in a linear sucrose gradient. N-Terminal amino acid sequence determination identified two proteins of M r 41 000 and M r 40 000 as the phaE Cv and phaC Cv translational products, respectively, of C. vinosum D. In a previous study it was shown that both proteins are required for the expression opf poly(3-hydroxyalkanoic acid) synthase activity. The N-terminus of the third protein ( M r 17 000) exhibited no homology to other proteins. Lysozyme, which was during purification of the granules, exhibited a strong affinity to PHB granules and was identified as the fourth protein enriched with the granules. 相似文献
13.
Cloning and Mapping of a Novel Nodulation Region from Bradyrhizobium japonicum by Genetic Complementation of a Deletion Mutant 总被引:4,自引:2,他引:2 下载免费PDF全文
The phenotypes of a set of Bradyrhizobium japonicum 110 mutants with large deletions in the region of symbiotic gene cluster I were tested. The majority of the mutants showed a delayed nodulation on soybean and, by mixed-infection experiments, were found to be strongly reduced in their competitiveness. Phenotypic comparison of mutants with different deletion endpoints allowed a preliminary localization of two genomic regions, called nod-1 and nod-2, which were required for normal nodulation on soybean. Loss of nod-1 was found to result in a Nod− phenotype on cowpea, mung bean, and siratro. A recombinant cosmid was identified which fully restored nodulation ability of a mutant lacking nod-1. Using Tn5-containing derivatives and subclones of this cosmid for complementation, we delimited the nod-1 region to a DNA segment of 3.1 to 3.5 kilobase pairs. 相似文献
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Matthias Laska 《Primates; journal of primatology》1996,37(4):457-465
The purpose of this study was to test the influence of sex, age, social rank, matriline membership, posture, and visual and
tactual motor control on manual preferences inSaimiri sciureus. A well-established social group of 12 squirrel monkeys, aged 2 to 14 yrs and consisting of two matrilines with social rank
known for each animal, was presented with four different food-reaching tasks and assessed for hand preferences with a minimum
of 100 reaches per animal.
Frequency of occurrence of hand preferences at the group level and degree of hand preferences at the individual level depended
on posture and on whether the reaching act took place under visual or tactual guidance. Sex, age, social rank, and matriline
membership were not found to determine frequency of occurrence, direction or degree of hand preferences with the exception
of one task in which a significant negative correlation between the degree of hand preference and age was found. Nine out
of 12 monkeys showed task-dependent changes in the hand they used preferentially while only three animals preferred the same
hand in all four tasks. Significant preferences for the use of right or left hand on a given task were distributed almost
equally between individuals. Thus, the results of this study suggest task-specific demands like posture and/or whether reaching
was visually or tactually guided to be the major correlates of hand preferences in food-reaching tasks in squirrel monkeys. 相似文献
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Matthias Liebergesell Alexander Steinbüchel 《Applied microbiology and biotechnology》1993,38(4):493-501
From a genomic library of Thiocystis violaceae strain 2311 in L47, two adjacent EcoRI restriction fragments of 5361 base pairs (bp) and of 1978 bp were cloned. The 5361-bp EcoRI restriction fragment hybridized with a DNA fragment harbouring the Alcaligenes eutrophus poly(3-hydroxyalkanoate) (PHA) synthase operon (phbCAB) and restored the ability to synthesize and accumulate PHA in PHA-negative mutants derived from A. eutrophus. The nucleotide sequence analysis of both fragments revealed five open-reading frames (ORFs); at least three of them are probably relevant for PHA biosynthesis. The amino acid sequences of the putative proteins deduced from these genes indicate that they encode a -ketothiolase [phbA
Tv, relative molecular mass (Mr) 40850], which exhibited 87.3% amino acid identify with the -ketothiolase from Chromatium vinosum. The amino acid sequences of the putative proteins deduced from ORF2Tv (Mr 41 450) and phbC
Tv (Mr 39 550), which were located upstream of and antilinear to phbA
Tv, exhibited 74.7% and 87.6% amino acid identify, respectively, with the corresponding gene products of C. vinosum. Downstream of and antilinear to phbC
Tv was located ORF5, which encodes for a protein of high relative molecular mass (Mr 76428) of unknown function. With respect to the divergent organisation of ORF2Tv and phbC
Tv on one side and of phbA
Tv on the other side and from the homologies of the putative gene products, this region of the T. violaceae genome resembled very much the corresponding region of C. vinosum, which was identified recently.
Correspondence to: A. Steinbüchel 相似文献
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Eduardo Moreno-Jiménez Fernando T. Maestre Maren Flagmeier Emilio Guirado Miguel Berdugo Felipe Bastida Marina Dacal Paloma Díaz-Martínez Raúl Ochoa-Hueso César Plaza Matthias C. Rillig Thomas W. Crowther Manuel Delgado-Baquerizo 《Global Change Biology》2023,29(2):522-532
Soil micronutrients are capital for the delivery of ecosystem functioning and food provision worldwide. Yet, despite their importance, the global biogeography and ecological drivers of soil micronutrients remain virtually unknown, limiting our capacity to anticipate abrupt unexpected changes in soil micronutrients in the face of climate change. Here, we analyzed >1300 topsoil samples to examine the global distribution of six metallic micronutrients (Cu, Fe, Mn, Zn, Co and Ni) across all continents, climates and vegetation types. We found that warmer arid and tropical ecosystems, present in the least developed countries, sustain the lowest contents of multiple soil micronutrients. We further provide evidence that temperature increases may potentially result in abrupt and simultaneous reductions in the content of multiple soil micronutrients when a temperature threshold of 12–14°C is crossed, which may be occurring on 3% of the planet over the next century. Altogether, our findings provide fundamental understanding of the global distribution of soil micronutrients, with direct implications for the maintenance of ecosystem functioning, rangeland management and food production in the warmest and poorest regions of the planet. 相似文献