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SuhB
''suhB'', also known as ''mmgR'' (makes more granules regulator), is a non-coding RNA found multiple times in the ''Agrobacterium tumefaciens'' genome and related alpha-proteobacteria. Other non-coding RNAs uncovered in the same analysis include '' speF'', '' ybhL'', ''metA'', and ''serC''. Several studies in '' Sinorhizobium meliloti'' showed that the ''suhB'' element is indeed a non-coding RNA. It was first detected by Northern blot and called ''Sm8RNA'', then in an RNAseq study and referred to as ''SmelC689''. The mutant (lacking the small RNA) phenotype's cytoplasm contains a higher content of polyhydroxybutyrate (PBH) storage granules than the wild type strain. The sRNA is required to limit the PBH intracellular accumulation when the nitrogen-fixing '' Sinorhizobium meliloti'' is converting surplus carbon to nitrogen his needs to be modified, carbon cannot be converted to nitrogen/sup>. Further study confirmed that ''suhB'' fine-tunes the regulation of PBH storage. North ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SpeF Leader
SpeF is a putative ''cis''-acting element identified in several gram negative alpha proteobacteria. It is proposed to be involved in regulating expression of genes involved in polyamide biosynthesis. SpeF is one of five putative regulatory elements identified by a computational screen of ''Agrobacterium tumefaciens'' and other alpha-proteobacterial genomes for conserved sequence motifs in operon leaders. In the majority of species analysed it is located in the leader of an operon containing the speF gene an ornithine decarboxylase enzyme that catalyses one of the first steps in polyamine biosynthesis. However, the authors did not detect binding of metabolites related to this pathway (L-ornithine, L-lysine, meso-diaminopimelate, putrescine, cadaverine, or spermidine Spermidine is a polyamine compound () found in ribosomes and living tissues and having various metabolic functions within organisms. It was originally isolated from semen. Function Spermidine is an aliphatic pol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agrobacterium Tumefaciens
''Agrobacterium radiobacter'' (more commonly known as ''Agrobacterium tumefaciens'') is the causal agent of crown gall disease (the formation of tumours) in over 140 species of eudicots. It is a rod-shaped, Gram-negative soil bacterium. Symptoms are caused by the insertion of a small segment of DNA (known as the T-DNA, for 'transfer DNA', not to be confused with tRNA that transfers amino acids during protein synthesis), from a plasmid into the plant cell, which is incorporated at a semi-random location into the plant genome. Plant genomes can be engineered by use of '' Agrobacterium'' for the delivery of sequences hosted in T-DNA binary vectors. ''Agrobacterium tumefaciens'' is an Alphaproteobacterium of the family Rhizobiaceae, which includes the nitrogen-fixing legume symbionts. Unlike the nitrogen-fixing symbionts, tumor-producing ''Agrobacterium'' species are pathogenic and do not benefit the plant. The wide variety of plants affected by ''Agrobacterium'' makes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
YbhL Leader
The YbhL leader is a putative structured RNA element that is found upstream of the uncharacterized YbhL membrane protein in alpha-proteobacteria. Other non-coding RNAs uncovered in the same analysis include: speF, suhB ''suhB'', also known as ''mmgR'' (makes more granules regulator), is a non-coding RNA found multiple times in the ''Agrobacterium tumefaciens'' genome and related alpha-proteobacteria. Other non-coding RNAs uncovered in the same analysis include ..., metA and serC. References External links * Cis-regulatory RNA elements {{molecular-cell-biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Structure
Protein secondary structure is the three dimensional form of ''local segments'' of proteins. The two most common secondary structural elements are alpha helices and beta sheets, though beta turns and omega loops occur as well. Secondary structure elements typically spontaneously form as an intermediate before the protein folds into its three dimensional tertiary structure. Secondary structure is formally defined by the pattern of hydrogen bonds between the amino hydrogen and carboxyl oxygen atoms in the peptide backbone. Secondary structure may alternatively be defined based on the regular pattern of backbone dihedral angles in a particular region of the Ramachandran plot regardless of whether it has the correct hydrogen bonds. The concept of secondary structure was first introduced by Kaj Ulrik Linderstrøm-Lang at Stanford in 1952. Other types of biopolymers such as nucleic acids also possess characteristic secondary structures. Types The most common secondary st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Small RNA
Small RNA (sRNA) are polymeric RNA molecules that are less than 200 nucleotides in length, and are usually non-coding. RNA silencing is often a function of these molecules, with the most common and well-studied example being RNA interference (RNAi), in which endogenously expressed microRNA (miRNA) or exogenously derived small interfering RNA (siRNA) induces the degradation of complementary messenger RNA. Other classes of small RNA have been identified, including piwi-interacting RNA (piRNA) and its subspecies repeat associated small interfering RNA (rasiRNA). Small RNA "is unable to induce RNAi alone, and to accomplish the task it must form the core of the RNA–protein complex termed the RNA-induced silencing complex (RISC), specifically with Argonaute protein". Small RNA have been detected or sequenced using a range of techniques, including directly by MicroRNA sequencing on several sequencing platforms, or indirectly through genome sequencing and analysis. Identification of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EcpR1 SRNA
EcpR1 (elongated cell phenotype RNA1) is a ''trans-''encoded small non-coding RNA in the plant-symbiotic '' Sinorhizobium meliloti'', previously named SmelC291, SmrC10, or Sra33. According to its overproduction phenotype it was renamed Elongated Cell Phenotype RNA1. Induced by stress, EcpR1 negatively regulates cell cycle master regulatory genes ''dnaA'' and ''gcrA'' at post-transcriptional level by base pairing between its strongly conserved GC-rich loop and the target mRNAs. It is suggested that EcpR1 connects stress adaptation and cell cycle progression. See also * SuhB ''suhB'', also known as ''mmgR'' (makes more granules regulator), is a non-coding RNA found multiple times in the ''Agrobacterium tumefaciens'' genome and related alpha-proteobacteria. Other non-coding RNAs uncovered in the same analysis include ... * RcsR1 small RNA Further reading {{Reflist Non-coding RNA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catabolite Repression
Carbon catabolite repression, or simply catabolite repression, is an important part of global control system of various bacteria and other microorganisms. Catabolite repression allows microorganisms to adapt quickly to a preferred (rapidly metabolizable) carbon and energy source first. This is usually achieved through inhibition of synthesis of enzymes involved in catabolism of carbon sources other than the preferred one. The catabolite repression was first shown to be initiated by glucose and therefore sometimes referred to as the glucose effect. However, the term "glucose effect" is actually a misnomer since other carbon sources are known to induce catabolite repression. ''Escherichia coli'' Catabolite repression was extensively studied in '' Escherichia coli''. ''E. coli'' grows faster on glucose than on any other carbon source. For example, if ''E. coli'' is placed on an agar plate containing only glucose and lactose, the bacteria will use glucose first and lactose second. W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beta-galactosidase
β-Galactosidase (EC 3.2.1.23, lactase, beta-gal or β-gal; systematic name β-D-galactoside galactohydrolase), is a glycoside hydrolase enzyme that catalyzes hydrolysis of terminal non-reducing β-D-galactose residues in β-D-galactosides. β-Galactosides include carbohydrates containing galactose where the glycosidic bond lies above the galactose molecule. Substrates of different β-galactosidases include ganglioside GM1, lactosylceramides, lactose, and various glycoproteins. Function β-Galactosidase is an exoglycosidase which hydrolyzes the β-glycosidic bond formed between a galactose and its organic moiety. It may also cleave fucosides and arabinosides but with much lower efficiency. It is an essential enzyme in the human body. Deficiencies in the protein can result in galactosialidosis or Morquio B syndrome. In '' E. coli'', the ''lacZ'' gene is the structural gene for β-galactosidase; which is present as part of the inducible system ''lac'' operon which is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetralin
Tetralin (1,2,3,4-tetrahydronaphthalene) is a hydrocarbon having the chemical formula C10H12. It is a partially hydrogenated derivative of naphthalene. It is a colorless liquid that is used as a hydrogen-donor solvent. Production Tetralin is produced by the catalytic hydrogenation of naphthalene. Although nickel catalysts are traditionally employed, many variations have been evaluated. Over-hydrogenation converts tetralin into decahydronaphthalene (decalin). Rarely encountered is dihydronaphthalene (dialin). Laboratory methods In a classic named reaction called the Darzens tetralin synthesis, named for Auguste Georges Darzens (1926), derivatives can be prepared by intramolecular electrophilic aromatic substitution reaction of a 1-aryl-4-pentene using concentrated sulfuric acid, Uses Tetralin is used as a hydrogen-donor solvent, for example in coal liquifaction. It functions as a source of H2, which is transferred to the coal. The partially hydrogenated coal is more ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alphaproteobacteria
Alphaproteobacteria is a class of bacteria in the phylum Pseudomonadota (formerly Proteobacteria). The Magnetococcales and Mariprofundales are considered basal or sister to the Alphaproteobacteria. The Alphaproteobacteria are highly diverse and possess few commonalities, but nevertheless share a common ancestor. Like all ''Proteobacteria'', its members are gram-negative and some of its intracellular parasitic members lack peptidoglycan and are consequently gram variable. Characteristics The Alphaproteobacteria are a diverse taxon and comprises several phototrophic genera, several genera metabolising C1-compounds (''e.g.'', ''Methylobacterium'' spp.), symbionts of plants (''e.g.'', '' Rhizobium'' spp.), endosymbionts of arthropods (''Wolbachia'') and intracellular pathogens (''e.g. Rickettsia''). Moreover, the class is sister to the protomitochondrion, the bacterium that was engulfed by the eukaryotic ancestor and gave rise to the mitochondria, which are organelles in eukaryoti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hfq Protein
The Hfq protein (also known as HF-I protein) encoded by the ''hfq'' gene was discovered in 1968 as an ''Escherichia coli'' host factor that was essential for replication of the bacteriophage Qβ. It is now clear that Hfq is an abundant bacterial RNA binding protein which has many important physiological roles that are usually mediated by interacting with Hfq binding sRNA. In ''E. coli'', Hfq mutants show multiple stress response related phenotypes. The Hfq protein is now known to regulate the translation of two major stress transcription factors ( σS (RpoS) and σE (RpoE) ) in Enterobacteria. It also regulates sRNA in ''Vibrio cholerae'', a specific example being MicX sRNA. In ''Salmonella typhimurium'', Hfq has been shown to be an essential virulence factor as its deletion attenuates the ability of ''S.typhimurium'' to invade epithelial cells, secrete virulence factors or survive in cultured macrophages. In ''Salmonella'', Hfq deletion mutants are also non motile and exhibit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinorhizobium Meliloti
''Ensifer meliloti'' (formerly ''Rhizobium meliloti'' and ''Sinorhizobium meliloti'') are an aerobic, Gram-negative, and diazotrophic species of bacteria. ''S. meliloti'' are motile and possess a cluster of peritrichous flagella. ''S. meliloti'' fix atmospheric nitrogen into ammonia for their legume symbionts, such as alfalfa. ''S. meliloti'' forms a symbiotic relationship with legumes from the genera ''Medicago'', ''Melilotus'' and '' Trigonella'', including the model legume ''Medicago truncatula''. This symbiosis promotes the development of a plant organ, termed a root nodule. Because soil often contains a limited amount of nitrogen for plant use, the symbiotic relationship between ''S. meliloti'' and their legume hosts has agricultural applications. These techniques reduce the need for inorganic nitrogenous fertilizers. Symbiosis Symbiosis between ''S. meliloti'' and its legume hosts begins when the plant secretes an array of betaines and flavonoids into the rhizosphere: 4, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
