BIOPAX Ontology

Contents:


Class Definitions

This section of the HTML version of the ontology contains the class definitions of the ontology. Each class defines a type of entity. A class is defined to have a set of slots, where each slot defines attributes and properties that may be used by an instance of that class.

Slots are inherited by a class from its parent classes. Usually this HTML form of the ontology shows only the names of the slots at each class, with links provided to the full definition of the slot in the slot section of the ontology. However, when the definition of a slot is changed within a class with respect to its parent, the full definition of the slot is shown.

Class: entity

Any concept that we will refer to as a discrete unit when describing biological pathways. e.g. a pathway, interaction or physical entity.

Subclasses: interaction, physicalEntity, pathway

Slots:

Class: interaction

One or two sets of entities and some relationship between them. A relationship exists between two or more entities and is not defined without the entities. The relationship does not have to be a physical relationship. It can be another type, such as logical, temporal, genetic, etc.

Supperclasses: entity

Subclasses: control, conversion, genetic, equivalenceClass, molecularAssociation, co-occurrence

Slots:

Class: control

The control of a process (e.g. enzyme catalysis controls a biochemical reaction, gene regulation controls gene expression).

Supperclasses: interaction

Subclasses: enzymeCatalysis, transportCatalysis, geneRegulation

Slots:

Class: enzymeCatalysis

Describes the catalysis by an enzyme of a particular reaction. Instances of this class describe properties of a pairing between an enzyme and a reaction. For example, a bifunctional enzyme that catalyzes two different reactions would be linked to two instances of the enzymeCatalysis class to describe the different properties of each function of that enzyme. Enzyme catalysis controls biochemicalReaction and together these classes can be used to describe typical metabolic pathways.

Supperclasses: control

Slots:

Class: transportCatalysis

Control of the process of transportation. An active or passive transporter can facilitate a translocation event.

Supperclasses: control

Slots:

Class: geneRegulation

The process of gene regulation by a transcription factor. A transcription factor binds upstream

Supperclasses: control

Slots:

Class: conversion

A conversion process, which converts one set of entities to another set (e.g. a biochemical reaction converts substrates to products, the process of complex assembly converts single molecules to a complex, transport converts entities in one compartment to the same entities in another compartment).

Supperclasses: interaction

Subclasses: biochemicalReaction, transport, translation, transcription, complexAssembly

Slots:

 

VALUE-TYPE: entity
SLOT-NAME-SYNONYMS: reactants, input

 

VALUE-TYPE: entity
SLOT-NAME-SYNONYMS: products, output

Class: biochemicalReaction

A biochemical reaction is a reaction in which substrates are written in terms of sums of species. This is what is typically done in biochemistry, and, in principle, all of the EC reactions should be biochemical reactions. Example: ATP + H2O = ADP + Pi. In this reaction, ATP is considered to be an equilibrium mixture of several species, namely ATP4-, HATP3-, H2ATP2-, MgATP2-, MgHATP-, and Mg2ATP. Additional species may also need to be considered if other ions (e.g. Ca2+) that bind ATP are present. Similar considerations apply to ADP and to inorganic phosphate (Pi). When writing biochemical reactions, it is important not to attach charges to the biochemical reactants and not to include ions such as H+ and Mg2+ in the equation. The reaction is written in the direction specified by the EC nomenclature system, if applicable, regardless of the physiological direction(s) in which the reaction proceeds.

Supperclasses: conversion

Slots:

For biochemical reactions, this slot refers to the standard transformed Gibbs energy change for a reaction written in terms of biochemical reactants (sums of species), delta-G'o.

delta-G'o = -RT lnK' and
delta-G'o = delta-H'o - T delta-S'o

delta-G'o has units of kJ/mol. Like K', it is a function of temperature (T), ionic strength (I), pH, and pMg (pMg = -log10[Mg2+]). Therefore, these quantities must be specified, and values for DELTA-G for biochemical reactions are represented as 5-tuples of the form (delta-G'o T I pH pMg). This slot may have multiple values, representing different measurements for delta-G'o obtained under the different experimental conditions listed in the 5-tuple.

VALUE-TYPE: LIST

For biochemical reactions, this slot refers to the standard transformed enthalpy change for a reaction written in terms of biochemical reactants (sums of species), delta-H'o.

delta-G'o = delta-H'o - T delta-S'o

VALUE-TYPE: NUMBER

For biochemical reactions, this slot refers to the standard transformed entropy change for a reaction written in terms of biochemical reactants (sums of species), delta-S'o.

delta-G'o = delta-H'o - T delta-S'o

VALUE-TYPE: NUMBER

The measured equilibrium constant for a biochemical reaction, encoded by the slot KEQ, is actually the apparent equilibrium constant, K'. Concentrations in the equilibrium constant equation refer to the total concentrations of all forms of particular biochemical reactants. For example, in the equilibrium constant equation for the biochemical reaction in which ATP is hydrolyzed to ADP and inorganic phosphate:

K' = [ADP][Pi]/[ATP],

the concentration of ATP refers to the total concentration of all of the following species:

[ATP] = [ATP4-] + [HATP3-] + [H2ATP2-] + [MgATP2-] + [MgHATP-] + [Mg2ATP].

The apparent equilibrium constant is formally dimensionless, and can be kept so by inclusion of as many of the terms (1 mol/dm3) in the numerator or denominator as necessary. It is a function of temperature (T), ionic strength (I), pH, and pMg (pMg = -log10[Mg2+]). Therefore, these quantities must be specified, and values for KEQ for biochemical reactions are represented as 5-tuples of the form (K' T I pH pMg). This slot may have multiple values, representing different measurements for K' obtained under the different experimental conditions listed in the 5-tuple.

VALUE-TYPE: NUMBER

Class: transport

The process of transport from one spatial location to another, typically within or at

Supperclasses: conversion

Slots:

Class: translation

Process of translation. This is useful to describe translation when details are unknown.

Supperclasses: conversion

Slots:

Class: transcription

The process of transcription. This is useful to describe transcription when details are unknown.

Supperclasses: conversion

Slots:

Class: complexAssembly

A step in the process of complex assembly. This is not the same as a complex, which is a physical object, called molecular association in the interaction class hierarchy.

Supperclasses: conversion

Slots:

Class: genetic

A genetic interaction (e.g. a synthetic lethal interaction). An interaction between elements of a genotype that results in a change in phenotype.

Supperclasses: interaction

Subclasses: synthetic, epistasis, suppression

Slots:

Class: synthetic

A synthetic genetic interaction. Two genes have a synthetic phenotype if each gene separately mutated has no phenotype, but when both genes are mutated at the same time, the phenotype exists.

Supperclasses: genetic

Slots:

Class: epistasis

An epistatic interaction occurs when an allele at one locus renders the genotype at a second locus irrelevant - the phenotype will be dictated by the genotype of the epistatic gene alone. (This definition from

Supperclasses: genetic

Slots:

Class: suppression

A suppressor is generally defined as a mutation that completely or partially restores the mutant phenotype of another mutation. (This definition from

Supperclasses: genetic

Slots:

Class: equivalenceClass

A set of entities that can be considered equivalent in some context (e.g. a set of paralogs that can replace each other as enzymes in a biochemical reaction, a set of enzymes that may not be homologs, but are functionally identical e.g. glucose-6-phosphatase).

Supperclasses: interaction

Slots:

Class: molecularAssociation

An association between a set of molecules (e.g. Arp2-Arp3 protein-protein interaction; protein complex e.g. the result of a co-immunoprecipitation experiment; hexokinase-glucose).

Supperclasses: interaction

Slots:

Class: co-occurrence

The co-occurrence of entities in some context. That context could be time, space, a sentence, sequence similarity space, etc. (e.g. colocalization of a few receptors e.g. in a GPI anchored lipid raft; co-migration of cells; genes expressed at the same time.)

Supperclasses: interaction

Subclasses: co-localization, co-incidence

Slots: