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Xenortide
The xenortides (A-D) are a class of linear peptides isolated from the bacterium '' Xenorhabdus nematophila'',{{Cite journal, last=Lang, first=Gerhard, last2=Kalvelage, first2=Tim, last3=Peters, first3=Arne, last4=Wiese, first4=Jutta, last5=Imhoff, first5=Johannes F., date=2008-06-01, title=Linear and Cyclic Peptides from the Entomopathogenic Bacterium Xenorhabdus nematophilus, journal=Journal of Natural Products, volume=71, issue=6, pages=1074–1077, doi=10.1021/np800053n, pmid=18491867, issn=0163-3864 a symbiont of the entomopathogenic nematode ''Steinernema carpocapsae''. This class of compounds is known for their insect virulence and cytotoxic biological activities. The tryptamide containing compounds (xenortides B and D) show higher biological activity than the phenylethylamides (xenortides A and C). The most biologically active compound was found to be xenortide B with a potency of less than 1.6 μM activity against '' Trypanosoma brucei rhodesiense'' (sleeping sickness) and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenortide Biosynthesis
The xenortides (A-D) are a class of linear peptides isolated from the bacterium '' Xenorhabdus nematophila'',{{Cite journal, last=Lang, first=Gerhard, last2=Kalvelage, first2=Tim, last3=Peters, first3=Arne, last4=Wiese, first4=Jutta, last5=Imhoff, first5=Johannes F., date=2008-06-01, title=Linear and Cyclic Peptides from the Entomopathogenic Bacterium Xenorhabdus nematophilus, journal=Journal of Natural Products, volume=71, issue=6, pages=1074–1077, doi=10.1021/np800053n, pmid=18491867, issn=0163-3864 a symbiont of the entomopathogenic nematode ''Steinernema carpocapsae''. This class of compounds is known for their insect virulence and cytotoxic biological activities. The tryptamide containing compounds (xenortides B and D) show higher biological activity than the phenylethylamides (xenortides A and C). The most biologically active compound was found to be xenortide B with a potency of less than 1.6 μM activity against '' Trypanosoma brucei rhodesiense'' (sleeping sickness) an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flavin Reductase (NADH)
Flavin reductase (NADH) (, ''NADH-dependent flavin reductase'', ''flavin:NADH oxidoreductase'') is an enzyme with systematic name ''flavin:NAD+ oxidoreductase''. This enzyme catalyses the following chemical reaction : reduced flavin + NAD+ \rightleftharpoons flavin + NADH + H+ The Escherichia coli ''Escherichia coli'' (),Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. also known as ''E. coli'' (), is a Gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus '' Esc ... enzyme reduces free flavins by NADH. References External links * {{Portal bar, Biology, border=no EC 1.5.1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biosynthesis
Biosynthesis is a multi-step, enzyme-catalyzed process where substrates are converted into more complex products in living organisms. In biosynthesis, simple compounds are modified, converted into other compounds, or joined to form macromolecules. This process often consists of metabolic pathways. Some of these biosynthetic pathways are located within a single cellular organelle, while others involve enzymes that are located within multiple cellular organelles. Examples of these biosynthetic pathways include the production of lipid membrane components and nucleotides. Biosynthesis is usually synonymous with anabolism. The prerequisite elements for biosynthesis include: precursor compounds, chemical energy (e.g. ATP), and catalytic enzymes which may require coenzymes (e.g.NADH, NADPH). These elements create monomers, the building blocks for macromolecules. Some important biological macromolecules include: proteins, which are composed of amino acid monomers joined via peptide bon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tryptophan
Tryptophan (symbol Trp or W) is an α-amino acid that is used in the biosynthesis of proteins. Tryptophan contains an α-amino group, an α- carboxylic acid group, and a side chain indole, making it a polar molecule with a non-polar aromatic beta carbon substituent. It is essential in humans, meaning that the body cannot synthesize it and it must be obtained from the diet. Tryptophan is also a precursor to the neurotransmitter serotonin, the hormone melatonin, and vitamin B3. It is encoded by the codon UGG. Like other amino acids, tryptophan is a zwitterion at physiological pH where the amino group is protonated (–; pKa = 9.39) and the carboxylic acid is deprotonated ( –COO−; pKa = 2.38). Humans and many animals cannot synthesize tryptophan: they need to obtain it through their diet, making it an essential amino acid. Function Amino acids, including tryptophan, are used as building blocks in protein biosynthesis, and proteins are required to sustain life. Man ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenylalanine
Phenylalanine (symbol Phe or F) is an essential α-amino acid with the formula . It can be viewed as a benzyl group substituted for the methyl group of alanine, or a phenyl group in place of a terminal hydrogen of alanine. This essential amino acid is classified as neutral, and nonpolar because of the inert and hydrophobic nature of the benzyl side chain. The L-isomer is used to biochemically form proteins coded for by DNA. Phenylalanine is a precursor for tyrosine, the monoamine neurotransmitters dopamine, norepinephrine (noradrenaline), and epinephrine (adrenaline), and the skin pigment melanin. It is encoded by the codons UUU and UUC. Phenylalanine is found naturally in the milk of mammals. It is used in the manufacture of food and drink products and sold as a nutritional supplement for its analgesic and antidepressant effects. It is a direct precursor to the neuromodulator phenethylamine, a commonly used dietary supplement. As an essential amino acid, phenylalanine is n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decarboxylation
Decarboxylation is a chemical reaction that removes a carboxyl group and releases carbon dioxide (CO2). Usually, decarboxylation refers to a reaction of carboxylic acids, removing a carbon atom from a carbon chain. The reverse process, which is the first chemical step in photosynthesis, is called carboxylation, the addition of CO2 to a compound. Enzymes that catalyze decarboxylations are called decarboxylases or, the more formal term, carboxy-lyases (Enzyme Commission number, EC number 4.1.1). In organic chemistry The term "decarboxylation" usually means replacement of a carboxyl group () with a hydrogen atom: :RCO2H -> RH + CO2 Decarboxylation is one of the oldest known organic reactions. It is one of the processes assumed to accompany pyrolysis and destructive distillation. Metal salts, especially copper compounds, facilitate the reaction via the intermediacy of metal carboxylate complexes. Decarboxylation of aryl carboxylates can generate the equivalent of the correspond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiolation
In organic chemistry, a thiol (; ), or thiol derivative, is any organosulfur compound of the form , where R represents an alkyl or other organic substituent. The functional group itself is referred to as either a thiol group or a sulfhydryl group, or a sulfanyl group. Thiols are the sulfur analogue of alcohols (that is, sulfur takes the place of oxygen in the hydroxyl () group of an alcohol), and the word is a blend of "''thio-''" with "alcohol". Many thiols have strong odors resembling that of garlic or rotten eggs. Thiols are used as odorants to assist in the detection of natural gas (which in pure form is odorless), and the "smell of natural gas" is due to the smell of the thiol used as the odorant. Thiols are sometimes referred to as mercaptans () or mercapto compounds, a term introduced in 1832 by William Christopher Zeise and is derived from the Latin ('capturing mercury')''Oxford American Dictionaries'' (Mac OS X Leopard). because the thiolate group () bonds very strongly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methylation
In the chemical sciences, methylation denotes the addition of a methyl group on a substrate, or the substitution of an atom (or group) by a methyl group. Methylation is a form of alkylation, with a methyl group replacing a hydrogen atom. These terms are commonly used in chemistry, biochemistry, soil science, and the biological sciences. In biological systems, methylation is catalyzed by enzymes; such methylation can be involved in modification of heavy metals, regulation of gene expression, regulation of protein function, and RNA processing. In vitro methylation of tissue samples is also one method for reducing certain histological staining artifacts. The reverse of methylation is demethylation. In biology In biological systems, methylation is accomplished by enzymes. Methylation can modify heavy metals, regulate gene expression, RNA processing and protein function. It has been recognized as a key process underlying epigenetics. Methanogenesis Methanogenesis, the process th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adenylation
Adenylylation, more commonly known as AMPylation, is a process in which an adenosine monophosphate (AMP) molecule is covalently attached to the amino acid side chain of a protein. This covalent addition of AMP to a hydroxyl side chain of the protein is a posttranslational modification. Adenylylation involves a phosphodiester bond between a hydroxyl group of the molecule undergoing adenylylation, and the phosphate group of the adenosine monophosphate nucleotide (i.e. adenylic acid). Enzymes that are capable of catalyzing this process are called AMPylators. The known amino acids to be targeted in the protein are tyrosine and threonine, and sometimes serine. When charges on a protein undergo a change, it affects the characteristics of the protein, normally by altering its shape via interactions of the amino acids which make up the protein. AMPylation can have various effects on the protein. These are properties of the protein like, stability, enzymatic activity, co-factor binding, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aminopeptidase
Aminopeptidases are enzymes that catalyze the cleavage of amino acids from the amino terminus (N-terminus) of proteins or peptides (exopeptidases). They are widely distributed throughout the animal and plant kingdoms and are found in many subcellular organelles, in cytosol, and as membrane components. Aminopeptidases are used in essential cellular functions. Many, but not all, of these peptidases are zinc metalloenzymes. Some aminopeptidases are monomeric, and others are assemblies of relatively high mass (50 kDa) subunits. cDNA sequences are available for several aminopeptidases and a crystal structure of the open state of human endoplasmic reticulum Aminopeptidase 1 ERAP1 is presented here. Amino acid sequences determined directly or deduced from cDNAs indicate some amino acid sequence homologies in organisms as diverse as ''Escherichia coli'' and mammals, particularly in catalytically important residues or in residues involved in metal ion binding. One important aminopeptidas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenorhabdus Nematophila
''Xenorhabdus'' is a genus of motile, gram-negative bacteria from the family of the Morganellaceae. All the species of the genus are only known to live in symbiosis with soil entomopathogenic nematodes from the genus ''Steinernema''. Although no free-living forms of ''Xenorhabdus'' have ever been isolated outside of the nematode host, the benefits for the bacteria are still unknown. However, it has been demonstrated that the nematode can't establish within its insect host without the bacteria. The tripartite ''Xenorhabdus''-nematode-insect interaction represents a model system in which both mutualistic and pathogenic processes can be studied in a single bacterial species. In the laboratory, some species are virulent even when artificially injected into the insect host, whereas others species need the nematode to affect the insect. Lifecycle # In the non-infestant-stage nematode living in the soil, ''Xenorhabdus'' spp. are carried in a specialized region of the intestine, ter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Entomopathogenic Nematode
Entomopathogenic nematodes (EPN) are a group of nematodes (thread worms), that cause death to insects. The term ''entomopathogenic'' has a Greek origin, with ''entomon'', meaning ''insect'', and '' pathogenic'', which means ''causing disease''. They are animals that occupy a bio control middle ground between microbial pathogens and predator/parasitoids, and are habitually grouped with pathogens, most likely because of their symbiotic relationship with bacteria. Although many other parasitic thread worms cause diseases in living organisms (sterilizing or otherwise debilitating their host), entomopathogenic nematodes, are specific in only infecting insects. Entomopathogenic nematodes (EPNs) live parasitically inside the infected insect host, and so they are termed as ''endoparasitic''. They infect many different types of insects living in the soil like the larval forms of moths, butterflies, flies and beetles as well as adult forms of beetles, grasshoppers and crickets. EPNs have b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
