In E. coli DNA replication is carried out by the DNA polymerase III holoenzyme. This holoenzyme is composed of many different protein subunits. One of these subunits, the sliding clamp, is attached to the DNA by a seven subunit sliding clamp loader that utilizes ATP hydrolysis for this purpose [8]. The sliding clamp selectively binds primer:template junctions and is used to help promote the recruitment of DNA polymerase once bound [8]. It has been shown that sliding clamp loader complexes can have DNA polymerase chaperone capabilities and multiple ATP binding sites that can increase the recruitment of the polymerase 100-1000 fold [9].
An exoenzyme, or extracellular enzyme, is an enzyme that is secreted by a cell and functions outside of that cell. Exoenzymes are produced by both prokaryotic and eukaryotic cells and have been shown to be a critical component of many biological processes. Most often these enzymes are involved in the breakdown of larger macromolecules. The breakdown of these larger macromolecules is critical for allowing their constituents to pass through the cell membrane and enter into the cell. For humans and other complex organisms this process is best characterized by the digestive system in which solid food is broken down [15] by exoenzymes into small molecules that are able to enter into cells and be utilized for various cellular functions. In addition to this integral role in biological systems, different classes of microbial exoenzymes have been used by humans since pre-historic times for such diverse purposes as food production, biofuels, textile production and in the paper industry [16]. Another important role that microbial exoenzymes serve is in the natural ecology and bioremediation of terrestial and marine [17] environments.
Very limited information is available about the original discovery of exoenzymes. According to Merriam-Webster dictionary, the term "exoenzyme" was first recognized in the English language in 1908 [18]. The book "Intracellular Enzymes: A Course of Lectures Given in the Physiological," by Horace Vernon is thought to be the first publication using this word in that year [19]. Based on the book, it can be assumed that the first known exoenzymes were pepsin and trypsin, as both are mentioned by Vernon to have been discovered by scientists Briike and Kiihne before 1908 [20].
Examples of extracellular enzymes:
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In E. coli DNA replication is carried out by the DNA polymerase III holoenzyme. This holoenzyme is composed of many different protein subunits. One of these subunits, the sliding clamp, is attached to the DNA by a seven subunit sliding clamp loader that utilizes ATP hydrolysis for this purpose [8]. The sliding clamp selectively binds primer:template junctions and is used to help promote the recruitment of DNA polymerase once bound [8]. It has been shown that sliding clamp loader complexes can have DNA polymerase chaperone capabilities and multiple ATP binding sites that can increase the recruitment of the polymerase 100-1000 fold [9].
An exoenzyme, or extracellular enzyme, is an enzyme that is secreted by a cell and functions outside of that cell. Exoenzymes are produced by both prokaryotic and eukaryotic cells and have been shown to be a critical component of many biological processes. Most often these enzymes are involved in the breakdown of larger macromolecules. The breakdown of these larger macromolecules is critical for allowing their constituents to pass through the cell membrane and enter into the cell. For humans and other complex organisms this process is best characterized by the digestive system in which solid food is broken down [15] by exoenzymes into small molecules that are able to enter into cells and be utilized for various cellular functions. In addition to this integral role in biological systems, different classes of microbial exoenzymes have been used by humans since pre-historic times for such diverse purposes as food production, biofuels, textile production and in the paper industry [16]. Another important role that microbial exoenzymes serve is in the natural ecology and bioremediation of terrestial and marine [17] environments.
Very limited information is available about the original discovery of exoenzymes. According to Merriam-Webster dictionary, the term "exoenzyme" was first recognized in the English language in 1908 [18]. The book "Intracellular Enzymes: A Course of Lectures Given in the Physiological," by Horace Vernon is thought to be the first publication using this word in that year [19]. Based on the book, it can be assumed that the first known exoenzymes were pepsin and trypsin, as both are mentioned by Vernon to have been discovered by scientists Briike and Kiihne before 1908 [20].
Examples of extracellular enzymes:
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help)CS1 maint: multiple names: authors list (
link)
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cite web}}
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help)
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cite web}}
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(
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{{
cite web}}
: Check date values in: |accessdate=
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