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Exonuclease Type A
Exonucleases are enzymes that work by cleaving nucleotides one at a time from the end (exo) of a polynucleotide chain. A hydrolysis, hydrolyzing reaction that breaks phosphodiester bonds at either the 3′ or the Directionality (molecular biology), 5′ end occurs. Its close relative is the endonuclease, which cleaves phosphodiester bonds in the middle (endo) of a polynucleotide chain. Eukaryotes and prokaryotes have three types of exonucleases involved in the normal turnover of mRNA: XRN1 (gene), 5′ to 3′ exonuclease (Xrn1), which is a dependent Decapping complex, decapping protein; 3′ to 5′ exonuclease, an independent protein; and poly(A)-specific 3′ to 5′ exonuclease. In both archaea and eukaryotes, one of the main routes of RNA degradation is performed by the multi-protein exosome complex, which consists largely of 3′ to 5′ exoribonucleases. Significance to polymerase RNA polymerase II is known to be in effect during transcriptional termination; it works w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poly I Structure
Poly, from the Greek πολύς meaning "many" or "much", may refer to: Businesses * China Poly Group Corporation, a Chinese business group, and its subsidiaries: ** Poly Property, a Hong Kong incorporated Chinese property developer ** Poly Real Estate, a Chinese real estate developer ** Poly Technologies, a defense manufacturing company * Poly (company), formerly Polycom, an American communications technology company People * Poly (footballer) (1906-1986), full name Policarpo Ribeiro de Oliveira, Brazilian footballer * Natasha Poly (born 1985), stage name of Russian supermodel Natalya Sergeyevna Polevshchikova * Poly Styrene (1957–2011), stage name of British musician Marianne Joan Elliott-Said Polytechnic * Hong Kong Polytechnic University, locally known as Poly * Polytechnic Heights, Fort Worth, Texas, neighborhood locally known as Poly * Polytechnic Institute of NYU (now New York University Tandon School of Engineering), locally known as Poly * '' The Rensselaer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNA Polymerase I
DNA polymerase I (or Pol I) is an enzyme that participates in the process of prokaryotic DNA replication. Discovered by Arthur Kornberg in 1956, it was the first known DNA polymerase (and the first known of any kind of polymerase). It was initially characterized in '' E. coli'' and is ubiquitous in prokaryotes. In ''E. coli'' and many other bacteria, the gene In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protei ... that encodes Pol I is known as ''polA''. The ''E. coli'' Pol I enzyme is composed of 928 amino acids, and is an example of a processive enzyme — it can sequentially catalyze multiple polymerisation steps without releasing the single-stranded template. The physiological function of Pol I is mainly to support repair of damaged DNA, but it also contributes to connectin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mus Musculus
The house mouse (''Mus musculus'') is a small mammal of the rodent family Muridae, characteristically having a pointed snout, large rounded ears, and a long and almost hairless tail. It is one of the most abundant species of the genus ''Mus (genus), Mus''. Although a wild animal, the house mouse has benefited significantly from associating with human habitation to the point that truly wild populations are significantly less common than the synanthropic populations near human activity. The house mouse has been domestication, domesticated as the pet or fancy mouse, and as the laboratory mouse, which is one of the most important model organisms in biology and medicine. The complete mouse reference genome was Whole genome sequencing, sequenced in 2002. Characteristics House mice have an adult body length (nose to base of tail) of and a tail length of . The weight is typically . In the wild they vary in color from grey and light brown to black (individual hairs are actually Agouti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Budding Yeast
''Saccharomyces cerevisiae'' () (brewer's yeast or baker's yeast) is a species of yeast (single-celled fungal microorganisms). The species has been instrumental in winemaking, baking, and brewing since ancient times. It is believed to have been originally isolated from the skin of grapes. It is one of the most intensively studied eukaryotic model organisms in molecular and cell biology, much like ''Escherichia coli'' as the model bacterium. It is the microorganism which causes many common types of fermentation. ''S. cerevisiae'' cells are round to ovoid, 5–10 μm in diameter. It reproduces by budding. Many proteins important in human biology were first discovered by studying their homologs in yeast; these proteins include cell cycle proteins, signaling proteins, and protein-processing enzymes. ''S. cerevisiae'' is currently the only yeast cell known to have Berkeley bodies present, which are involved in particular secretory pathways. Antibodies against ''S. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CCR4-Not
Carbon Catabolite Repression 4—Negative On TATA-less, or CCR4-Not, is a multiprotein complex that functions in gene expression. The complex has multiple enzymatic activities as both a poly(A) 3′-5′ exonuclease and a ubiquitin ligase. The exonuclease activity of CCR4-Not shortens the poly(A) tail found at 3' end of almost every eukaryotic mRNA. The complex is present both in the nucleus where it regulates transcription and in the cytoplasm where it associates with translating ribosomes and RNA processing bodies. In mammalian cell, it has a function in the regulation of the cell cycle, chromatin modification, activation and inhibition of transcription initiation, control of transcription elongation, RNA export, nuclear RNA surveillance, and DNA damage repair in nucleus. Ccr4–Not complex plays an important role in mRNA decay and protein quality control in the cytoplasm. Subunits The human CCR4-Not complex is composed of structural (non-catalytic) subunits and those t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Buchnera Aphidicola
''Buchnera aphidicola'', a member of the Pseudomonadota and the only species in the genus ''Buchnera'', is the primary endosymbiont of aphids, and has been studied in the pea aphid, '' Acyrthosiphon pisum''. ''Buchnera'' is believed to have had a free-living, Gram-negative ancestor similar to a modern Enterobacterales, such as ''Escherichia coli''. ''Buchnera'' is 3 μm in diameter and has some of the key characteristics of its Enterobacterales relatives, such as a Gram-negative cell wall. However, unlike most other Gram-negative bacteria, ''Buchnera'' lacks the genes to produce lipopolysaccharides for its outer membrane. The long association with aphids and the limitation of crossover events due to strictly vertical transmission has seen the deletion of genes required for anaerobic respiration, the synthesis of amino sugars, fatty acids, phospholipids, and complex carbohydrates. This has resulted not only in one of the smallest known genomes of any living organism, but al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNA Replication
In molecular biology, DNA replication is the biological process of producing two identical replicas of DNA from one original DNA molecule. DNA replication occurs in all life, living organisms, acting as the most essential part of heredity, biological inheritance. This is essential for cell division during growth and repair of damaged tissues, while it also ensures that each of the new cells receives its own copy of the DNA. The cell possesses the distinctive property of division, which makes replication of DNA essential. DNA is made up of a nucleic acid double helix, double helix of two Complementary DNA, complementary DNA strand, strands. DNA is often called double helix. The double helix describes the appearance of a double-stranded DNA which is composed of two linear strands that run opposite to each other and twist together. During replication, these strands are separated. Each strand of the original DNA molecule then serves as a template for the production of its counterpart, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salmonella
''Salmonella'' is a genus of bacillus (shape), rod-shaped, (bacillus) Gram-negative bacteria of the family Enterobacteriaceae. The two known species of ''Salmonella'' are ''Salmonella enterica'' and ''Salmonella bongori''. ''S. enterica'' is the type species and is further divided into six subspecies that include over 2,650 serotypes. ''Salmonella'' was named after Daniel Elmer Salmon (1850–1914), an American veterinary surgeon. ''Salmonella'' species are non-Endospore, spore-forming, predominantly motility, motile enterobacteriaceae, enterobacteria with cell diameters between about 0.7 and 1.5 micrometre, μm, lengths from 2 to 5 μm, and peritrichous flagella (all around the cell body, allowing them to move). They are chemotrophs, obtaining their energy from Redox, oxidation and reduction reactions, using organic sources. They are also facultative aerobic organism, facultative anaerobes, capable of generating adenosine triphosphate with oxygen ("aerobically") ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homologous Recombination
Homologous recombination is a type of genetic recombination in which genetic information is exchanged between two similar or identical molecules of double-stranded or single-stranded nucleic acids (usually DNA as in Cell (biology), cellular organisms but may be also RNA in viruses). Homologous recombination is widely used by cells to accurately DNA repair, repair harmful DNA breaks that occur on both strands of DNA, known as double-strand breaks (DSB), in a process called homologous recombinational repair (HRR). Homologous recombination also produces new combinations of DNA sequences during meiosis, the process by which eukaryotes make gamete cells, like sperm and ovum, egg cells in animals. These new combinations of DNA represent genetic variation in offspring, which in turn enables populations to Adaptation, adapt during the course of evolution. Homologous recombination is also used in horizontal gene transfer to exchange genetic material between different strains and species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exonuclease V
Exodeoxyribonuclease V (EC 3.1.11.5, RecBCD, Exonuclease V, ''Escherichia coli'' exonuclease V, ''E. coli'' exonuclease V, gene recBC endoenzyme, RecBC deoxyribonuclease, gene recBC DNase, gene recBCD enzymes) is an enzyme of ''E. coli'' that initiates recombinational repair from potentially lethal double strand breaks in DNA which may result from ionizing radiation, replication errors, endonucleases, oxidative damage, and a host of other factors. The RecBCD enzyme is both a helicase that unwinds, or separates the strands of DNA, and a nuclease that makes single-stranded nicks in DNA. It catalyses exonucleolytic cleavage (in the presence of ATP) in either 5′- to 3′- or 3′- to 5′-direction to yield 5′-phosphooligonucleotides. Structure The enzyme complex is composed of three different subunits called RecB, RecC, and RecD and hence the complex is named RecBCD (Figure 1). Before the discovery of the ''recD'' gene, the enzyme was known as “RecBC.” Each subunit is en ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deoxyribonuclease IV
Deoxyribonuclease IV (phage-T4-induced) (, ''endodeoxyribonuclease IV (phage T4-induced)'', ''E. coli endonuclease IV'', ''endodeoxyribonuclease'', ''redoxyendonuclease'', ''deoxriboendonuclease'', ''Escherichia coli endonuclease II'', ''endonuclease II'', ''DNA-adenine-transferase'') is catalyzes the degradation nucleotides in DsDNA by attacking the 5'-terminal end. Deoxyribonuclease IV is a type of deoxyribonuclease that has both an exonucleolytic and an endonucleolytic activity. It functions at abasic or apurinic-apyrimidinic sites when the cell is undergoing nucleotide excision repair pathway. In addition, the endonuclease IV consists of several activities such as AP endonuclease, 3'-diesterase, 3'->5' exonuclease, and 3'phosphatase. The endonuclease IV is encoded by denB of bacteriophage T4 and its binding sequence is 5′-dT, , dCdAdCdTdTdC-3′. It has been discovered that serine 176 residue plays a crucial role in increasing the hydrolysis rate of the endonuclease of a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exonuclease VII
The enzyme exodeoxyribonuclease VII (EC 3.1.11.6, ''Escherichia coli'' exonuclease VII, ''E. coli'' exonuclease VII, endodeoxyribonuclease VII, exodeoxyribonuclease VII) is a bacterial exonuclease enzyme. It is composed of two nonidentical subunits; one large subunit and 4 small ones. that catalyses exonucleolytic cleavage in either 5′- to 3′- or 3′- to 5′-direction to yield nucleoside 5′-phosphates. The large subunit also contains an ''N''-terminal OB-fold domain that binds to nucleic acids. The widely used quinolone antibiotics induce DNA damage in bacterial cells by trapping DNA gyrase (an essential type II topoisomerase), leading to blocked gyrase cleavage complexes. Exonuclease VII participates in repairing such DNA damage by resolving the trapped cleavage complexes. When ''Escherichia coli ''Escherichia coli'' ( )Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. is a gram-negative, facultative anaerobic, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
