Related Experiment Video
Updated: Jul 18, 2026
08:01
A Web Tool for Generating High Quality Machine-readable Biological Pathways
Published on: February 8, 2017
Functional cartography of complex metabolic networks.
Roger Guimerà1, Luís A Nunes Amaral
1NICO and Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, USA.
Nature
|February 25, 2005
Summary
This study introduces a novel network analysis method to map functional modules and node roles in biological networks. It reveals that cross-module metabolites are more evolutionarily conserved than highly connected hubs.
Area of Science:
- Systems biology
- Bioinformatics
- Computational biology
Background:
- Biological databases are rapidly expanding due to high-throughput techniques.
- Interpreting complex biological network data presents a significant scientific challenge.
Purpose of the Study:
- To develop a methodology for extracting and visualizing information from complex biological networks.
- To identify functional modules and classify nodes based on their connection patterns within and between modules.
Main Methods:
- A network analysis approach was developed to create a 'cartographic representation' of complex networks.
- The methodology was applied to analyze metabolic networks of twelve organisms across three superkingdoms.
Main Results:
- The analysis identified functional modules and universal node roles within metabolic networks.
- Typically, 80% of nodes were found to be confined within their respective modules.
- Metabolites connecting different modules showed higher evolutionary conservation than intra-module hubs.
Conclusions:
- The proposed method effectively maps complex biological networks, revealing modular organization and node functions.
- Different evolutionary pressures act on nodes with distinct roles.
- Inter-module metabolites represent a conserved class of biological molecules crucial for network stability.
Related Concept Videos
02:26Protein Networks
An organism can have thousands of different proteins, and these proteins must cooperate to ensure the health of an organism. Proteins bind to other proteins and form complexes to carry out their functions. Many proteins interact with multiple other proteins creating a complex network of protein interactions.
These interactions can be represented through maps depicting protein-protein interaction networks, represented as nodes and edges. Nodes are circles that are representative of a protein,...
These interactions can be represented through maps depicting protein-protein interaction networks, represented as nodes and edges. Nodes are circles that are representative of a protein,...
02:26Protein Networks
An organism can have thousands of different proteins, and these proteins must cooperate to ensure the health of an organism. Proteins bind to other proteins and form complexes to carry out their functions. Many proteins interact with multiple other proteins creating a complex network of protein interactions.
These interactions can be represented through maps depicting protein-protein interaction networks, represented as nodes and edges. Nodes are circles that are representative of a protein,...
These interactions can be represented through maps depicting protein-protein interaction networks, represented as nodes and edges. Nodes are circles that are representative of a protein,...
01:07Ladder Diagrams: Complexation Equilibria
Ladder diagrams are useful for evaluating equilibria involving metal-ligand complexes. The vertical scale of the ladder diagram represents the concentration of unreacted or free ligand, pL. The horizontal lines on the scale depict the log of stepwise formation constants for metal-ligand complexes and indicate the dominant species in all the regions.
The formation constant, K1, for the formation of Cd(NH3)2+ complex from cadmium and ammonia is 3.55 × 102. Log K1 (i.e. pNH3) is 2.55, and...
The formation constant, K1, for the formation of Cd(NH3)2+ complex from cadmium and ammonia is 3.55 × 102. Log K1 (i.e. pNH3) is 2.55, and...
01:25Network Function of a Circuit
Frequency response analysis in electrical circuits provides vital insights into a circuit's behavior as the frequency of the input signal changes. The transfer function, a mathematical tool, is instrumental in understanding this behavior. It defines the relationship between phasor output and input and comes in four types: voltage gain, current gain, transfer impedance, and transfer admittance. The critical components of the transfer function are the poles and zeros.
01:21Manipulation and Analysis
GIS manipulation and analysis functions are vital for decision-making and planning. These activities range from data retrieval tasks, such as selecting information based on specific criteria, to advanced analytical techniques that address complex spatial problems.One critical GIS analysis method is overlaying, which combines multiple data layers to examine impacts. For example, overlaying a river-dammed lake boundary with road networks can identify affected infrastructure. Another common...
01:30Graphs of Functions
Graphs of functions provide a visual representation of how output values change in response to varying inputs. Each point on the graph corresponds to an ordered pair, where the x-coordinate (independent variable) determines the horizontal position and the y-coordinate (dependent variable) determines the vertical position. Linear functions like y = x give a straight line, indicating a constant rate of change.Nonlinear functions display more complex behaviors. Even power functions generate...