PUL ID

PUL0100

PubMed

9405618, Proc Natl Acad Sci U S A. 1997 Dec 23;94(26):14367-71. doi: 10.1073/pnas.94.26.14367.

Characterization method

transposon mutagenesis, growth assay

Genomic accession number

NZ_CP027060.1

Nucelotide position range

4090005-4095238

Substrate

chitobiose

Loci

chbBCARFG

Species

Escherichia coli/562

Degradation or Biosynthesis

degradation

Cluster number

1

Gene name

Gene position

Gene type

Found by CGCFinder?

chbG 1 - 750 (-) CDS No
- 763 - 2115 (-) CAZyme: GH4 Yes
chbR 2220 - 3059 (-) TF: DBD-Pfam|HTH_AraC,DBD-Pfam|HTH_AraC,DBD-SUPERFAMILY|0035607 Yes
chbA 3070 - 3420 (-) TC: gnl|TC-DB|P69791|4.A.3.2.1 Yes
chbC 3471 - 4829 (-) TC: gnl|TC-DB|P17334|4.A.3.2.1 Yes
chbB 4914 - 5234 (-) TC: gnl|TC-DB|P69795|4.A.3.2.1 Yes

PUL ID

PUL0100

PubMed

9405618, Proc Natl Acad Sci U S A. 1997 Dec 23;94(26):14367-71. doi: 10.1073/pnas.94.26.14367.

Title

Wild-type Escherichia coli grows on the chitin disaccharide, N,N'-diacetylchitobiose, by expressing the cel operon.

Author

Keyhani NO, Roseman S

Abstract

We report here that wild-type Escherichia coli can grow on the chitin disaccharide, N,N'-diacetylchitobiose (GlcNAc)2, as the sole source of carbon. Transposon mutants were isolated that were unable to ferment (GlcNAc)2 but grew normally on the monosaccharide GlcNAc. One such mutant was used to screen a wild-type E. coli genomic cosmid library for restoration of (GlcNAc)2 fermentation. A partial sequence analysis of the isolated fragment mapped the clone to the (previously sequenced) E. coli genome between 39.0 and 39.2 min. The nucleotide ORFs at this region had been previously assigned to code for a "cryptic" cellobiose utilization (cel) operon. We report here, however, that functional analysis of the operon, including growth and chemotaxis, reveal that it encodes a set of proteins that are not cryptic, but are induced by (GlcNAc)2 and catabolize the disaccharide. We therefore propose to rename the cel operon as the chb (N,N'-diacetylchitobiose) operon, with the letter designation of the genes of the operon to be reassigned consistent with the nomenclature based on functional characterization of the gene products as follows: celA to chbB, celB to chbC, celC to chbA, celD to chbR, and celF to chbF. Furthermore, sequencing evidence indicates that the operon contains an additional gene of unknown function to be designated as chbG. Thus, the overall gene sequence is to be named chbBCARFG.