Proteomic insights into mannan degradation and protein secretion by the forest floor bacterium Chitinophaga pinensis
Journal article, 2017

Together with fungi, saprophytic bacteria are central to the decomposition and recycling of biomass in forest environments. The Bacteroidetes phylum is abundant in diverse habitats, and several species have been shown to be able to deconstruct a wide variety of complex carbohydrates. The genus Chid/lop/lap is often enriched in hotspots of plant and microbial biomass degradation. We present a proteomic assessment of the ability of Chitinophaga pinensis to grow on and degrade mannan polysaccharides, using an agarose plate-based method of protein collection to minimise contamination with exopolysaccharides and proteins from lysed cells, and to reflect the realistic setting of growth on a solid surface. We show that select Polysaccharide Utilisation Loci (PULs) are expressed in different growth conditions, and identify enzymes that may be involved in mannan degradation. By comparing proteomic and enzymatic profiles, we show evidence for the induced expression of enzymes and PULs in cells grown on mannan polysaccharides compared with cells grown on glucose. In addition, we show that the secretion of putative biomass-degrading enzymes during growth on glucose comprises a system for nutrient scavenging, which employs constitutively produced enzymes. Significance of this study: Chitinophaga pinensis belongs to a bacterial genus which is prominent in microbial communities in agricultural and forest environments, where plant and fungal biomass is intensively degraded. Such degradation is hugely significant in the recycling of carbon in the natural environment, and the enzymes responsible are of biotechnological relevance in emerging technologies involving the deconstruction of plant cell wall material. The bacterium has a comparatively large genome, which includes many uncharacterised carbohydrate -active enzymes. We present the first proteomic assessment of the biomass-degrading machinery of this species, focusing on mannan, an abundant plant cell wall hemicellulose. Our findings include the identification of several novel enzymes, which are promising targets for future biochemical characterisation. In addition, the data indicate the expression of specific Polysaccharide Utilisation Loci. induced in the presence of different growth substrates. We also highlight how a constitutive secretion of enzymes which deconstruct microbial biomass likely forms part of a nutrient scavenging process. (C) 2017 Elsevier B.V. All rights reseivecl.

Galactoglucomannan

cellvibrio-japonicus

Secretome

ller gl

substrate-specificity

Biochemistry & Molecular Biology

CAZyme

phanerochaete-chrysosporium

analytical chemistry

1959

hydrolase family

Label-free quantification

Chitinophaga pinensis

v31

p237

beta domain

gliding motility

cleary bv

system

konjac glucomannan

pa14 domain

v139

carbohydrate research

postia-placenta

1985

p426

Author

Johan Larsbrink

Chalmers, Biology and Biological Engineering, Industrial Biotechnology

Wallenberg Wood Science Center (WWSC)

T. R. Tuveng

Norwegian University of Life Sciences

P. B. Pope

Norwegian University of Life Sciences

Vincent Bulone

AlbaNova University Center

University of Adelaide

V. Eijsink

Norwegian University of Life Sciences

H. Brumer

Wallenberg Wood Science Center (WWSC)

Michael Smith Laboratories

AlbaNova University Center

Lauren S McKee

AlbaNova University Center

Wallenberg Wood Science Center (WWSC)

Journal of Proteomics

1874-3919 (ISSN)

Vol. 156 63-74

Driving Forces

Sustainable development

Subject Categories

Forest Science

Environmental Biotechnology

DOI

10.1016/j.jprot.2017.01.003

More information

Latest update

4/10/2019