Cell Rep: The assembly mechanism of microbial communities in metabolic division of labor

The famous economist Adam Smith pointed out in his classic book "The Wealth of Nations" that the division of labor is one of
the main ways to increase labor productivity and increase national wealth.
Like other higher biological groups, such as humans, the microbial community is a complex and highly organized "society.
"
Microbial metabolism drives the global biogeochemical cycle
.
In the microbial community, a metabolic pathway can be performed either by a single microbial population or by the division of labor between different populations, that is, the metabolic division of labor (MDOL, Figure 1).

Many important metabolic processes in nature, such as nitrification, anaerobic oxidation of methane and degradation of complex organic matter, are completed
in the form of metabolic division of labor.
However, little is known about how this metabolic behavior shapes microbial communities and how divisions of labor stabilize their existence
.
If microorganisms also have production lines, how to maintain them in an orderly manner? Professor Wu Xiaolei of the School of Engineering and Nie Yong's research group gave the answer through a series of studies: not suffering from widowhood but suffering from inequality
.

Figure 1: Construction principle of metabolic division of labor community

On September 27, 2022, Cell Reports magazine published a research paper
by Wu Xiaolei and Nie Yong's research group entitled "Even allocation of benefits stabilizes microbial community engaged in metabolic division of labor" 。 This paper constructs a theoretical framework that can be used to accurately predict the assembly of microbial communities with metabolic division of labor, and lays a theoretical foundation
for the design and regulation of artificial microbial communities by using metabolic division of labor strategy.

The research group of Wu Xiaolei and Nie Yong took the metabolic division of labor community of degrading complex organic substances as the research object, and analyzed the law of substrate characteristics regulating the construction of metabolic division of labor community (https://doi.
org/10.
1002/mlf2.
12025), as well as the spatial assembly characteristics of metabolic division of labor community (https://doi.
org/10.
1128/spectrum.
01944-21).

。 On the basis of these studies, based on the mathematical model describing the dynamics of the metabolic division of labor community, the research group established a more streamlined and comprehensive theoretical framework to predict the stability and assembly characteristics
of the community through rigorous mathematical derivation.
This framework (Figure 1) states that in order to maintain the stability of the metabolic division community, the strain responsible for the initial step in the linear metabolic pathway should have a growth advantage (m) over the strain that performs the last step, and the advantage (m) must be greater than the "privatization benefit" (n)
obtained by the last step strain.
For a stable metabolic division of labor community, perform the last step with a relative abundance of strains equal to the quotient
of n and m.
Through the genetic modification of model microbial strains, the naphthalene degradation and metabolic division community
was artificially constructed.
The analysis showed that the assembly of the metabolic division of labor microbial communities can be determined
by a limited number of parameters.
The theoretical framework derived from the mathematical model can accurately predict the stability and assembly characteristics
of the synthetic flora of two-step and multi-step naphthalene degradation metabolism.
This quantitative prediction law helps us understand the construction principle of natural microbial communities, and provides new insights
for the design and construction of stable microbial systems and the optimization of metabolic pathways.
An anonymous reviewer for this paper noted: "I believe this work has made an outstanding contribution
to the optimization of metabolic pathways in microbiome engineering.
As far as I know, this is the first time to combine mathematical models and experimental analysis to study the division of microbial metabolism, which is a perfect combination of
theory and experimental verification.
The mathematical principles obtained from the research are wonderful and strongly supported
by experimental data.
”

The first author of this paper is Miaoxiao Wang, Ph.
D.
of the School of Engineering in 2021 (currently engaged in postdoctoral research at ETH Zurich, Switzerland), and Xiaolei Wu and Yong Nie are the co-corresponding authors
of this paper.
Chen Xiaoli and Liu Xiaonan, doctoral students of the School of Engineering, participated in the analysis of
the research results.
Professor Martin Ackermann of the Swiss Federal Institute of Technology Zurich contributed
to the study.
This paper was awarded as an excellent paper
of "Jian Haoran Environmental Microbiology Fund" at the 23rd National Symposium on Environmental Microbiology.
The research was supported
by the National Key Research and Development Program of China (2018YFA0902100) and the China-Sweden International Cooperation and Exchange Program (32161133023).

Paper Information:

Miaoxiao Wang, Xiaoli Chen, Xiaonan Liu, Yuan Fang, Xin Zheng, Ting Huang, Yue-Qin Tang, Martin Ackermann, Yong Nie, Xiao-Lei Wu.
2022.
Even allocation of benefits stabilizes microbial community engaged in metabolic division of labor.
Cell Reports 40(13): 111410.
https://doi.
org/10.
1016/j.
celrep.
2022.
111410