TY - JOUR
T1 - β-glucan is a major growth substrate for human gut bacteria related to Coprococcus eutactus
AU - Alessi, Anna M
AU - Gray, Victoria
AU - Farquharson, Freda M
AU - Flores-López, Adriana
AU - Shaw, Sophie
AU - Stead, David
AU - Wegmann, Udo
AU - Shearman, Claire
AU - Gasson, Mike
AU - Collie-Duguid, Elaina SR
AU - Flint, Harry J
AU - Louis, Petra
N1 - Open Access via the Jisc Wiley Deal
Funding Information:
University of Aberdeen Rowett Institute
Institute of Food Research
Scottish Government Rural and Environment Science and Analytical Services Division
Acknowledgements
Freda M. Farquharson, Harry J. Flint and Petra Louis received financial support from the Scottish Government Rural and Environment Science and Analytical Services Division (RESAS). Anna M. Alessi received a PhD scholarship jointly funded by the Institute of Food Research (Norwich, UK, now Quadram Institute) and the Rowett Institute (University of Aberdeen, Aberdeen, UK). The authors wish to thank Gill Campbell and Pauline Young for their assistance with colony picking and screening metagenomic libraries, Brennan Martin at the Centre for Genome Enabled Biology and Medicine, University of Aberdeen, for performing the RNA sequencing, Evelyn Argo and Craig Pattinson for advice on sample preparation for proteomics work, Bekhal Kareem Sharif and Manon Le Merrer for help with growth experiments, Sylvia Duncan for the gift of acid‐swollen cellulose and for providing strains C. comes A2‐232 and SL7/1, Pat Bain for help with figure formats and Mike Peck and Bruce Pearson at the Institute for Food Research Norwich for helpful discussions.
PY - 2020/6/1
Y1 - 2020/6/1
N2 - A clone encoding carboxymethylcellulase activity was isolated during functional screening of a human gut metagenomic library using Lactococcus lactis MG1363 as heterologous host. The insert carried a glycoside hydrolase family 9 (GH9) catalytic domain with sequence similarity to a gene from Coprococcus eutactus ART55/1. Genome surveys indicated a limited distribution of GH9 domains among dominant human colonic anaerobes. Genomes of C. eutactus‐related strains harboured two GH9‐encoding and four GH5‐encoding genes, but the strains did not appear to degrade cellulose. Instead, they grew well on β‐glucans and one of the strains also grew on galactomannan, galactan, glucomannan and starch. Coprococcus comes and Coprococcus catus strains did not harbour GH9 genes and were not able to grow on β‐glucans. Gene expression and proteomic analysis of C. eutactus ART55/1 grown on cellobiose, β‐glucan and lichenan revealed similar changes in expression in comparison to glucose. On β‐glucan and lichenan only, one of the four GH5 genes was strongly upregulated. Growth on glucomannan led to a transcriptional response of many genes, in particular a strong upregulation of glycoside hydrolases involved in mannan degradation. Thus, β‐glucans are a major growth substrate for species related to C. eutactus, with glucomannan and galactans alternative substrates for some strains.
AB - A clone encoding carboxymethylcellulase activity was isolated during functional screening of a human gut metagenomic library using Lactococcus lactis MG1363 as heterologous host. The insert carried a glycoside hydrolase family 9 (GH9) catalytic domain with sequence similarity to a gene from Coprococcus eutactus ART55/1. Genome surveys indicated a limited distribution of GH9 domains among dominant human colonic anaerobes. Genomes of C. eutactus‐related strains harboured two GH9‐encoding and four GH5‐encoding genes, but the strains did not appear to degrade cellulose. Instead, they grew well on β‐glucans and one of the strains also grew on galactomannan, galactan, glucomannan and starch. Coprococcus comes and Coprococcus catus strains did not harbour GH9 genes and were not able to grow on β‐glucans. Gene expression and proteomic analysis of C. eutactus ART55/1 grown on cellobiose, β‐glucan and lichenan revealed similar changes in expression in comparison to glucose. On β‐glucan and lichenan only, one of the four GH5 genes was strongly upregulated. Growth on glucomannan led to a transcriptional response of many genes, in particular a strong upregulation of glycoside hydrolases involved in mannan degradation. Thus, β‐glucans are a major growth substrate for species related to C. eutactus, with glucomannan and galactans alternative substrates for some strains.
KW - BUTYRATE-PRODUCING BACTERIA
KW - RUMINOCOCCUS-CHAMPANELLENSIS
KW - CELLULOSE DEGRADATION
KW - ENDOGLUCANASE
KW - MICROBIOTA
KW - METAGENOMICS
KW - PHYLOGENIES
KW - PROPIONATE
KW - SECRETION
KW - GENOMICS
UR - http://www.scopus.com/inward/record.url?scp=85082074659&partnerID=8YFLogxK
U2 - 10.1111/1462-2920.14977
DO - 10.1111/1462-2920.14977
M3 - Article
C2 - 32141148
VL - 22
SP - 2150
EP - 2164
JO - Environmental Microbiology
JF - Environmental Microbiology
SN - 1462-2912
IS - 6
ER -