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1. Biochem the substance upon which an enzyme acts
2. Electronics the semiconductor base on which other material is deposited, esp in the construction of integrated circuits
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



(1) In biology, the base—an object or substance—to which sedentary animals and plants, including microorganisms, are attached.

(2) In biochemistry, a substance acted upon by enzymes. The term “substrate” refers to the primary and intermediate products of metabolism (metabolites) that take part in enzymatic transformations. Chemically, substrates may vary from simple molecules of hydrogen peroxide (H2O2) to highly complex molecules of proteins and nucleic acids.

During an enzymatic reaction, the substrate is activated and combines with the enzyme to form an enzyme-substrate complex, which decomposes and releases the products of the reaction. As a rule, a given enzyme activates only few substrates, a phenomenon called substrative specificity. Consequently, the name of a substrate is often the source for the name of the corresponding enzyme. For example, the enzyme that splits D-glucose-1-phosphate into glucose and phosphate is called D-glucose-1-phosphatase.

The substrative specificity of enzymes is determined by the structure of their active centers; substrates can directly affect the formation of these centers. The concentration of substrates is a factor in the regulation of enzymatic activity. Substrates and their analogues—substances similar in structure to the substrates —often induce the biosynthesis of the corresponding enzymes. Some analogues of substrates are specific inhibitors of enzymes.

(3) In microbiology, nutrient media for the growth of microorganisms.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.


The substance with which an enzyme reacts.
The foundation to which a sessile organism is attached.
The physical material on which a microcircuit is fabricated; used primarily for mechanical support and insulating purposes, as with ceramic, plastic, and glass substrates; however, semiconductor and ferrite substrates may also provide useful electrical functions.
Basic surface on which a material adheres, for example, paint or laminate.
(organic chemistry)
A compound with which a reagent reacts.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.


1. The underlying material to which a finish is applied, or by which it is supported.
2. A material upon which an adhesive, film, coating, etc., is applied.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.


The body or base layer of an integrated circuit, onto which other layers are deposited to form the circuit. The substrate is usually Silicon, though Sapphire is used for certain applications, particularly military, where radiation resistance is important. The substrate is originally part of the wafer from which the die is cut. It is used as the electrical ground for the circuit.
This article is provided by FOLDOC - Free Online Dictionary of Computing (


The base layer of a structure such as a chip, multichip module (MCM), printed circuit board or disk platter. Silicon is the most widely used substrate for chips. Fiberglass (FR4) is mostly used for printed circuit boards, and ceramic is used for MCMs. Disk substrates are typically aluminum, glass or plastic.
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References in periodicals archive ?
The analysts forecast the global lcd glass substrate market to exhibit a CAGR of 5.27% during the period 2019-2024.
With the recent trend of IoT (Internet of Things) and smartphones with greater functionality, the semiconductor package and module market is significantly expanding and the demand for substrate materials is also rapidly increasing.
In the case of acclimatization by nebulization, a substrate is desired that will rapidly drain excess water, i.e., with a high air filled porosity (AFP) (CALVETE et al., 2000).
The research team used model substrate Sic1PY and a novel nucleotide-substitution strategy to image the human proteasome in the action of substrate processing.
In the Wenzel model, cos [[theta].sup.*] = r cos [theta], where [[theta].sup.*] is the apparent contact angle of the sessile drop on the substrate, r is the roughness of the smooth substrate, and [theta] is the intrinsic contact angle (i.e., the contact angle for the ideal smooth substrate).
Thus, each plant should be matched to its own corresponding seedling substrate, and producers should not use a universal substrate for different seedlings (Luo et al., 2015; Zhao et al., 2012).
There are two layers of dielectric substrate which are made up of Rogers 4350 substrate with diameter of the metallized via 0.4 millimeters for the SW-HMSIW structure.
For nursery production, any substrate low in organic matter is not suitable due to low moisture holding capacity.
Due to the sharing of substrate resources, a single substrate failure will affect all the VNs sharing it.
This situation allows the teacher to delve deeper into the concept of enzyme-substrate complementarity during discussion--that specificity is determined not just by shape of the interface between an enzyme and a substrate, but also by the exact dimensions of each of the models to form a perfectly fitted enzyme-substrate complex.
Adults of Crepidula fornicata from the east coast of the United States and Crepipatella peruviana from Chile--our two study species--typically live in stacks, with smaller, younger individuals attached by the foot to larger, older individuals below; the bottom-most individual is attached by the foot to a rock or other hard substrate (Orton, 1912; Chaparro et al., 2004; Henry et al., 2010).