| Title |
The novel Streptomyces olivaceoviridis ABC transporter Ngc mediates uptake of N-acetylglucosamine and N,N'-diacetylchitobiose
|
|---|---|
| Published in |
Molecular Genetics and Genomics, April 2002
|
| DOI | 10.1007/s00438-002-0640-2 |
| Pubmed ID | |
| Authors |
X. Xiao, F. Wang, A. Saito, J. Majka, A. Schlösser, H. Schrempf |
| Abstract |
During cultivation in the presence of N-acetylglucosamine or chitin, Streptomyces olivaceoviridis mycelium efficiently takes up [(14)C]-labelled N-acetylglucosamine. Uptake of the labelled compound can be completely inhibited by unlabelled N-acetylglucosamine and partially by chitobiose. After extraction of the membrane with Triton X-100, two forms of a protein that binds to N-acetylglucosamine and N, N'-diacetylchitobiose (chitobiose) were purified to homogeneity by two consecutive rounds of anionic exchange chromatography. The protein was named NgcE. Using surface plasmon resonance, its binding parameters were determined. It showed highest affinity for N-acetylglucosamine (K(D)=8.28 x 10(-9) M) and for chitobiose (K(D)=2.87 x 10(-8) M). Varying equilibrium dissociation constants in the micromolecular range were ascertained for chitotetraose (K(D)=4.5 x 10(-6) M), chitopentaose (K(D)=1.03 x 10(-6) M) and chitohexaose (K(D)=3.02 x 10(-6) M); the lowest value was measured for chitotriose (K(D)=19.4 x 10(-6) M). After having determined the sequences of several internal peptides from the binding protein by Edman degradation, the corresponding ngcE gene, which encodes a predicted lipid-anchored protein, was identified by reverse genetics. Using a genomic phage library of S. olivaceoviridis genes encoding two other membrane proteins (named NgcF and NgcG) were identified adjacent to ngcE. Each of these is predicted to have six membrane-spanning helices and a consensus motif for integral membrane proteins characteristic of ABC transporters. In addition, the gene for a predicted regulator protein (NgcR) was detected. The ngcEFG operon lacks a gene for an ATP-hydrolysing protein. NgcE is a new member of the CUT-1 family of ABC transporters for carbohydrates. Comparative studies of the wild-type and a mutant strain carrying an insertion within the ngc operon clearly demonstrate that the Ngc system mediates the uptake of N-acetylglucosamine and chitobiose in vivo. |
Mendeley readers
The data shown below were compiled from readership statistics for 29 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| United States | 3 | 10% |
| Portugal | 1 | 3% |
| Unknown | 25 | 86% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Researcher | 12 | 41% |
| Student > Ph. D. Student | 6 | 21% |
| Student > Master | 4 | 14% |
| Student > Bachelor | 2 | 7% |
| Professor | 1 | 3% |
| Other | 2 | 7% |
| Unknown | 2 | 7% |
| Readers by discipline | Count | As % |
|---|---|---|
| Agricultural and Biological Sciences | 11 | 38% |
| Biochemistry, Genetics and Molecular Biology | 6 | 21% |
| Immunology and Microbiology | 2 | 7% |
| Environmental Science | 1 | 3% |
| Earth and Planetary Sciences | 1 | 3% |
| Other | 2 | 7% |
| Unknown | 6 | 21% |
Attention Score in Context
This research output has an Altmetric Attention Score of 3. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 09 March 2016.
All research outputs
#8,534,528
of 25,371,288 outputs
Outputs from Molecular Genetics and Genomics
#920
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Outputs of similar age
#43,248
of 128,676 outputs
Outputs of similar age from Molecular Genetics and Genomics
#2
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