Molecular characterization of a high-affinity xylobiose transporter of Streptomyces thermoviolaceus OPC-520 and its transcriptional regulation. 2004

Hiroshi Tsujibo, and Mitsuo Kosaka, and Sadao Ikenishi, and Takaji Sato, and Katsushiro Miyamoto, and Yoshihiko Inamori
Department of Microbiology, Osaka University of Pharmaceutical Sciences, Takatsuki, Osaka 569-1094, Japan. tsujibo@gly.oups.ac.jp

Streptomyces thermoviolaceus OPC-520 secretes two types of xylanases (StxI and StxII), an acetyl xylan esterase (StxIII), and an alpha-L-arabinofuranosidase (StxIV) in the presence of xylan. Xylan degradation products (mainly xylobiose) produced by the action of these enzymes entered the cell and were then degraded to xylose by an intracellular beta-xylosidase (BxlA). A gene cluster involved in xylanolytic system of the strain was cloned and sequenced upstream of and including a BxlA-encoding gene (bxlA). The gene cluster consisted of four different open reading frames organized in the order bxlE, bxlF, bxlG, and bxlA. Reverse transcriptase PCR analysis revealed that the gene cluster is transcribed as polycistronic mRNA. The deduced gene products, comprising BxlE (a sugar-binding lipoprotein), BxlF (an integral membrane protein), and BxlG (an integral membrane protein), showed similarity to components of the bacterial ATP-binding cassette (ABC) transport system; however, the gene for the ATP binding protein was not linked to the bxl operon. The soluble recombinant BxlE protein was analyzed for its binding activity for xylooligosaccharides. The protein showed high-level affinity for xylobiose (K(d) = 8.75 x 10(-9) M) and for xylotriose (K(d) = 8.42 x 10(-8) M). Antibodies raised against the recombinant BxlE recognized the detergent-soluble BxlE isolated from S. thermoviolaceus membranes. The deduced BxlF and BxlG proteins are predicted to be integral membrane proteins. These proteins contained the conserved EAA loop (between the fourth and the fifth membrane-spanning segments) which is characteristic of membrane proteins from binding-protein-dependent ABC transporters. In addition, the bxlR gene located upstream of the bxl operon was cloned and expressed in Escherichia coli. The bxlR gene encoded a 343-residue polypeptide that is highly homologous to members of the GalR/LacI family of bacterial transcriptional regulators. The purified BxlR protein specifically bound to a 4-bp inverted sequence overlapping the -10 region of the bxl operon. The binding of BxlR to the site was inhibited specifically by low concentrations of xylobiose. This site was also present in the region located between stxI and stxIV and in the upstream region of stxII. BxlR specifically bound to the regions containing the inverted sequence. These results suggest that BxlR might act as a repressor of the genes involved not only in the uptake system of xylan degradation products but also in xylan degradation of S. thermoviolaceus OPC-520.

UI MeSH Term Description Entries
D008969 Molecular Sequence Data Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories. Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D003001 Cloning, Molecular The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells. Molecular Cloning
D004187 Disaccharides Oligosaccharides containing two monosaccharide units linked by a glycosidic bond. Disaccharide
D005810 Multigene Family A set of genes descended by duplication and variation from some ancestral gene. Such genes may be clustered together on the same chromosome or dispersed on different chromosomes. Examples of multigene families include those that encode the hemoglobins, immunoglobulins, histocompatibility antigens, actins, tubulins, keratins, collagens, heat shock proteins, salivary glue proteins, chorion proteins, cuticle proteins, yolk proteins, and phaseolins, as well as histones, ribosomal RNA, and transfer RNA genes. The latter three are examples of reiterated genes, where hundreds of identical genes are present in a tandem array. (King & Stanfield, A Dictionary of Genetics, 4th ed) Gene Clusters,Genes, Reiterated,Cluster, Gene,Clusters, Gene,Families, Multigene,Family, Multigene,Gene Cluster,Gene, Reiterated,Multigene Families,Reiterated Gene,Reiterated Genes
D000595 Amino Acid Sequence The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION. Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D013302 Streptomyces A genus of bacteria that form a nonfragmented aerial mycelium. Many species have been identified with some being pathogenic. This genus is responsible for producing a majority of the ANTI-BACTERIAL AGENTS of practical value.
D014158 Transcription, Genetic The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION. Genetic Transcription
D014995 Xylosidases A group of enzymes that catalyze the hydrolysis of alpha- or beta-xylosidic linkages. EC 3.2.1.8 catalyzes the endo-hydrolysis of 1,4-beta-D-xylosidic linkages; EC 3.2.1.32 catalyzes the endo-hydrolysis of 1,3-beta-D-xylosidic linkages; EC 3.2.1.37 catalyzes the exo-hydrolysis of 1,4-beta-D-linkages from the non-reducing termini of xylans; and EC 3.2.1.72 catalyzes the exo-hydrolysis of 1,3-beta-D-linkages from the non-reducing termini of xylans. Other xylosidases have been identified that catalyze the hydrolysis of alpha-xylosidic bonds. Xylobiases,Xylan Hydrolases,Hydrolases, Xylan
D016366 Open Reading Frames A sequence of successive nucleotide triplets that are read as CODONS specifying AMINO ACIDS and begin with an INITIATOR CODON and end with a stop codon (CODON, TERMINATOR). ORFs,Protein Coding Region,Small Open Reading Frame,Small Open Reading Frames,sORF,Unassigned Reading Frame,Unassigned Reading Frames,Unidentified Reading Frame,Coding Region, Protein,Frame, Unidentified Reading,ORF,Open Reading Frame,Protein Coding Regions,Reading Frame, Open,Reading Frame, Unassigned,Reading Frame, Unidentified,Region, Protein Coding,Unidentified Reading Frames
D018528 ATP-Binding Cassette Transporters A family of MEMBRANE TRANSPORT PROTEINS that require ATP hydrolysis for the transport of substrates across membranes. The protein family derives its name from the ATP-binding domain found on the protein. ABC Transporter,ABC Transporters,ATP-Binding Cassette Transporter,ATP Binding Cassette Transporter,ATP Binding Cassette Transporters,Cassette Transporter, ATP-Binding,Transporter, ABC,Transporter, ATP-Binding Cassette,Transporters, ABC,Transporters, ATP-Binding Cassette

Related Publications

Hiroshi Tsujibo, and Mitsuo Kosaka, and Sadao Ikenishi, and Takaji Sato, and Katsushiro Miyamoto, and Yoshihiko Inamori
July 2007, Acta crystallographica. Section F, Structural biology and crystallization communications,
Hiroshi Tsujibo, and Mitsuo Kosaka, and Sadao Ikenishi, and Takaji Sato, and Katsushiro Miyamoto, and Yoshihiko Inamori
November 2000, Bioscience, biotechnology, and biochemistry,
Hiroshi Tsujibo, and Mitsuo Kosaka, and Sadao Ikenishi, and Takaji Sato, and Katsushiro Miyamoto, and Yoshihiko Inamori
June 2017, Journal of biochemistry,
Hiroshi Tsujibo, and Mitsuo Kosaka, and Sadao Ikenishi, and Takaji Sato, and Katsushiro Miyamoto, and Yoshihiko Inamori
October 2001, Protein expression and purification,
Hiroshi Tsujibo, and Mitsuo Kosaka, and Sadao Ikenishi, and Takaji Sato, and Katsushiro Miyamoto, and Yoshihiko Inamori
February 1993, Applied and environmental microbiology,
Hiroshi Tsujibo, and Mitsuo Kosaka, and Sadao Ikenishi, and Takaji Sato, and Katsushiro Miyamoto, and Yoshihiko Inamori
October 1998, Biochimica et biophysica acta,
Hiroshi Tsujibo, and Mitsuo Kosaka, and Sadao Ikenishi, and Takaji Sato, and Katsushiro Miyamoto, and Yoshihiko Inamori
June 2004, Bioscience, biotechnology, and biochemistry,
Hiroshi Tsujibo, and Mitsuo Kosaka, and Sadao Ikenishi, and Takaji Sato, and Katsushiro Miyamoto, and Yoshihiko Inamori
January 2000, Bioscience, biotechnology, and biochemistry,
Hiroshi Tsujibo, and Mitsuo Kosaka, and Sadao Ikenishi, and Takaji Sato, and Katsushiro Miyamoto, and Yoshihiko Inamori
November 1993, Gene,
Hiroshi Tsujibo, and Mitsuo Kosaka, and Sadao Ikenishi, and Takaji Sato, and Katsushiro Miyamoto, and Yoshihiko Inamori
January 1992, Applied and environmental microbiology,
Copied contents to your clipboard!