Enzrxn

This slot lists the enzyme whose activity is described in this frame. More specifically, the value of this slot is the key of a frame from the class [Protein-Complexes] or [Polypeptides].

Some enzymes catalyze only a particular reaction when they are components of a larger protein complex. For such an enzyme, this slot identifies the particular protein complex of which the enzyme must be a component.

The value of this slot is the key of a frame from the Reactions class -- the second half of the enzyme/reaction pair that the current frame describes. In fact, this slot can have multiple values, which encode the multiple reactions that one catalytic site of an enzyme catalyzes.

这里表示的是一个多对多的关系 即本对象表示的是Enzyme所指向的蛋白质分子可以催化本列表的所有反应，即某一个酶分子可以催化一系列反应 而对于每一个Reaction对象而言，其EnzymaticReaction也为一个列表，即某一个反应可以被几个酶分子进行催化

The values of this slot are members of the [Regulation] class, describing activator or inhibitor compounds for this enzymatic reaction.

The Michaelis constant (KM) of an enzyme is equal to the substrate concentration at which the rate of the reaction is at half of its maximum value. The Michaelis constant is an apparent dissociation constant of the enzyme-substrate complex, and thereby is an indicator of the affinity of an enzyme to a given substrate. Values of this slot are two-element lists of the form (cpd-frame Km) where cpd-frame is the frame id for a substrate of the reaction referred to by this enzymatic-reaction frame and Km is the Michaelis constant, a floating point number.

This slot specifies the directionality of a reaction. This slot is used in slightly different ways in class Reactions and Enzymatic-Reactions. In class Enzymatic-Reactions, the slot specifies information about the direction of the reaction associated with the enzymatic-reaction, by the associated enzyme. That is, the directionality information refers only to the case in which the reaction is catalyzed by that enzyme, and may be influenced by the regulation of that enzyme. The slot is particularly important to fill for reactions that are not part of a pathway, because for such reactions, the direction cannot be determined automatically, whereas for reactions within a pathway, the direction can be inferred from the pathway context. This slot aids the user and software in inferring the direction in which the reaction typically occurs in physiological settings, relative to the direction in which the reaction is stored in the database.

PHYSIOLOGICALLY-RELEVANT?