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P. White 《BMJ (Clinical research ed.)》1989,298(6682):1199-1200
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In this paper we report the observation of a rapidly developed vertebrate symbiosis involving ectoparasite cleaning by a native corvid of northern Australia, the Torresian crow Corvus orru , on a recently introduced bovid ungulate, the banteng Bos javanicus . Facultative symbioses benefiting both participants (mutualisms) between birds and mammals appear to be rare, despite the apparent advantages obtained by the participants (ecto-parasite removal from the host and food provision to the cleaner). On three separate dates we observed a total of four C. orru individuals eliciting facilitation behaviours by a total of ten female banteng to assist in the removal of ectoparasites. Our observations document the first-known incidence of facultative cleaning behaviour by a native bird species on a non-native, wild vertebrate that has developed in approximately 150 years since the banteng's introduction to Australia. 相似文献
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V L Vaughn R Wang C Fenselau H B White 《Biochemical and biophysical research communications》1987,147(1):115-119
The tryptic phosphopeptide of hen egg white riboflavin-binding protein has been found to exist as a mixture of peptides which differ only with respect to the number of covalently bound phosphoryl groups. Anion-exchange chromatography was used to separate homologues of the tryptic phosphopeptide of egg white riboflavin-binding protein. Four peptide peaks were obtained and analyzed using plasma desorption mass spectrometry. Molecular ions obtained agree closely with calculated molecular weight values for phosphopeptides with 8, 7 and 5 phosphoryl groups. Amino acid analyses showed that the octa- and hepta-phosphorylated peptides were pure and had the same amino acid compositions. 相似文献
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A 22-amino-acid peptide restores DNA-binding activity to dimerization-defective mutants of the estrogen receptor. 总被引:9,自引:5,他引:4 下载免费PDF全文
We have identified residues within the estrogen receptor that are required for dimerization and high-affinity DNA binding. A 22-amino-acid peptide encompassing these residues was sufficient to restore DNA-binding activity to a mutant receptor lacking most of the hormone-binding domain. Point mutagenesis of the fusion protein confirmed that this sequence continued to mediate dimerization in a manner similar to that within the native receptor, although its position relative to the DNA-binding domain was appreciably altered. 相似文献
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