Home Repository Download Help About Statistics Taxonomy Blastx
Links
PULDB
CAZy
dbCAN2
dbCAN-seq
run_dbcan
CAZypedia
PlantCAZyme
Cite: NAR/gkaa742 2020

Because CGCFinder predicted no CGC for this PUL, the gene cluster depicted below contains dbCAN2 and CGC signature predictions for all genes in the PUL, instead of a predicted CGC.


PUL General Information

Literature Information

PUL ID

PUL0671

PubMed

34731049, Appl Environ Microbiol. 2022 Jan 25;88(2):e0183721. doi: 10.1128/AEM.01837-21. Epub 2021 Nov 3.

Characterization method

gene deletion mutant and growth assay,enzyme activity assay,Western blot,qPCR

Genomic accession number

NC_008255.1

Nucelotide position range

1051545-1060308

Substrate

cellulose

Loci

CHU_RS04470-CHU_RS04490

Species

Cytophaga hutchinsonii ATCC 33406/985 

Degradation or Biosynthesis

degradation

Gene Name

Locus Tag

Protein ID

Gene Position

GenBank Contig Range

EC Number

- CHU_RS04470 WP_011584315.1 0 - 1617 (-) NC_008255.1:1051545-1053162 -
- CHU_RS18795 WP_177254166.1 1606 - 2143 (-) NC_008255.1:1053151-1053688 -
- CHU_RS04475 WP_177254165.1 2045 - 2852 (-) NC_008255.1:1053590-1054397 -
- CHU_RS04480 WP_011584316.1 3083 - 5276 (-) NC_008255.1:1054628-1056821 -
- CHU_RS04485 WP_011584317.1 5292 - 6069 (-) NC_008255.1:1056837-1057614 -
- CHU_RS04490 WP_011584318.1 6070 - 8764 (-) NC_008255.1:1057615-1060309 6.3.2.4

Cluster number

0

Gene name

Gene position

Gene type

Found by CGCFinder?

- 1 - 1617 (-) TC: gnl|TC-DB|A6H1F5|1.B.23.4.2 No
- 1607 - 2143 (-) TC: gnl|TC-DB|G0CIY2|9.B.18.1.1 No
- 2046 - 2852 (-) CDS No
- 3084 - 5276 (-) CDS No
- 5293 - 6069 (-) CDS No
- 6071 - 8764 (-) CDS No

PUL ID

PUL0671

PubMed

34731049, Appl Environ Microbiol. 2022 Jan 25;88(2):e0183721. doi: 10.1128/AEM.01837-21. Epub 2021 Nov 3.

Title

A Type IX Secretion System Substrate Involved in Crystalline Cellulose Degradation by Affecting Crucial Cellulose Binding Proteins in Cytophaga hutchinsonii.

Author

Gao L, Su Y, Song W, Zhang W, Qi Q, Lu X

Abstract

Cytophaga hutchinsonii is an abundant soil cellulolytic bacterium that uses a unique cellulose degradation mechanism different from those that involve free cellulases or cellulosomes. Though several proteins have been identified as important for cellulose degradation, the mechanism used by C. hutchinsonii to digest crystalline cellulose remains a mystery. In this study, chu_0922 was identified by insertional mutation and gene deletion as an important gene locus indispensable for crystalline cellulose utilization. Deletion of chu_0922 resulted in defects in crystalline cellulose utilization. The Delta0922 mutant completely lost the ability to grow on crystalline cellulose, even with extended incubation, and selectively utilized the amorphous region of cellulose, leading to increased crystallinity. As a protein secreted by the type IX secretion system (T9SS), CHU_0922 was found to be located on the outer membrane, and the outer membrane localization of CHU_0922 relied on the T9SS. Comparative analysis of the outer membrane proteins revealed that the abundance of several cellulose-binding proteins, including CHU_1276, CHU_1277, and CHU_1279, was reduced in the Delta0922 mutant. Further study showed that CHU_0922 is crucial for the full expression of the gene cluster containing chu_1276, chu_1277, chu_1278, chu_1279, and chu_1280 (cel9C), which is essential for cellulose utilization. Moreover, CHU_0922 is required for the cell surface localization of CHU_3220, a cellulose-binding protein that is essential for crystalline cellulose utilization. Our study provides insights into the complex system that C. hutchinsonii uses to degrade crystalline cellulose. IMPORTANCE The widespread aerobic cellulolytic bacterium Cytophaga hutchinsonii, belonging to the phylum Bacteroidetes, utilizes a novel mechanism to degrade crystalline cellulose. No genes encoding proteins specialized in loosening or disruption the crystalline structure of cellulose were identified in the genome of C. hutchinsonii, except for chu_3220 and chu_1557. The crystalline cellulose degradation mechanism remains enigmatic. This study identified a new gene locus, chu_0922, encoding a typical T9SS substrate that is essential for crystalline cellulose degradation. Notably, CHU_0922 is crucial for the normal transcription of chu_1276, chu_1277, chu_1278, chu_1279, and chu_1280 (cel9C), which play important roles in the degradation of cellulose. Moreover, CHU_0922 participates in the cell surface localization of CHU_3220. These results demonstrated that CHU_0922 plays a key role in the crystalline cellulose degradation network. Our study will promote the uncovering of the novel cellulose utilization mechanism of C. hutchinsonii.