
the three faces of the genetic code
... of incremental expansion. The ‘chemical’ challenge suggests that certain codon assignments were directly influenced by favorable chemical interactions between particular amino acids and short nucleic acid sequences, whereas lack of such interactions excluded other amino acids from proteins entirely. ...
... of incremental expansion. The ‘chemical’ challenge suggests that certain codon assignments were directly influenced by favorable chemical interactions between particular amino acids and short nucleic acid sequences, whereas lack of such interactions excluded other amino acids from proteins entirely. ...
Identification of a molecular component of the mitochondrial
... However, eukaryotic orthologues to Pat have not been identified in either the mitochondrial or nuclear genome [9]. An alternative scenario in eukaryotes could be that mitochondrial proteins are acetylated in the cytosol prior to mitochondrial import. However, as fasting and feeding result in a dynam ...
... However, eukaryotic orthologues to Pat have not been identified in either the mitochondrial or nuclear genome [9]. An alternative scenario in eukaryotes could be that mitochondrial proteins are acetylated in the cytosol prior to mitochondrial import. However, as fasting and feeding result in a dynam ...
Inhibition of Protein Kinases by Balanol: Specificity within the Serine
... affinity of balanol toward both isoforms of PKC. All of the balanol derivatives tested are five to six times more potent toward PKCbII than PKCa. In general, alterations in the structure of balanol emphasize the complementary nature of the interactions between balanol and kinases of the AGC group, a ...
... affinity of balanol toward both isoforms of PKC. All of the balanol derivatives tested are five to six times more potent toward PKCbII than PKCa. In general, alterations in the structure of balanol emphasize the complementary nature of the interactions between balanol and kinases of the AGC group, a ...
Mutations in a Signal Sequence for the Thylakoid Membrane Identify
... 1990; Simpson and Von Wettstein, 1989), insert into membranes. Because ribosomes are seen on the thylakoid membrane, it is assumed that chloroplast-encoded proteins are inserted cotranslationally (Chua et al., 1973; Willey et al., 1983). The machinery required for insertion has not been described, h ...
... 1990; Simpson and Von Wettstein, 1989), insert into membranes. Because ribosomes are seen on the thylakoid membrane, it is assumed that chloroplast-encoded proteins are inserted cotranslationally (Chua et al., 1973; Willey et al., 1983). The machinery required for insertion has not been described, h ...
47_Biochemistry of Connective Tissue
... First synthesized in precursor form of preprocollagen polypeptide chain in the ribosomes during translation The leader sequence of amino acids[signal peptide] in the preprocollagen directs it to enter the lumen of E.R In the lumen of E.R, the Signal peptide is cleaved to form procollagen. Th ...
... First synthesized in precursor form of preprocollagen polypeptide chain in the ribosomes during translation The leader sequence of amino acids[signal peptide] in the preprocollagen directs it to enter the lumen of E.R In the lumen of E.R, the Signal peptide is cleaved to form procollagen. Th ...
Identification, Expression and Characterization of Archaeal
... 3.3.3.4. Homology Relation of Cop-5 Modular Domains with Known Prototype Proteins .................................................................................................................... 51 3.3.4. Comparative Molecular Modeling of Modular Domains of Cop-5................... 53 3.3.4.1. G ...
... 3.3.3.4. Homology Relation of Cop-5 Modular Domains with Known Prototype Proteins .................................................................................................................... 51 3.3.4. Comparative Molecular Modeling of Modular Domains of Cop-5................... 53 3.3.4.1. G ...
Bluetongue virus: dissection of the polymerase complex
... globular VP5 protein to permeabilize the endosomal membrane via its amino terminal ‘pore-forming’ peptide, analogous to the fusion peptides of envelope viruses (Hassan et al., 2001; Forzan et al., 2004, 2007). The membrane penetration activity of VP5 was dramatically shown when VP5 was presented app ...
... globular VP5 protein to permeabilize the endosomal membrane via its amino terminal ‘pore-forming’ peptide, analogous to the fusion peptides of envelope viruses (Hassan et al., 2001; Forzan et al., 2004, 2007). The membrane penetration activity of VP5 was dramatically shown when VP5 was presented app ...
Are viruses a source of new protein folds for organisms? Virosphere
... time of the Cambrian explosion until today, could have been sampled by a viral gene during the written history of humankind. It is well known that protein structure is much more conserved than sequence ([41], quantified in ref. [42]). Thus, the interference between cellular and viral protein domains ...
... time of the Cambrian explosion until today, could have been sampled by a viral gene during the written history of humankind. It is well known that protein structure is much more conserved than sequence ([41], quantified in ref. [42]). Thus, the interference between cellular and viral protein domains ...
Beer Foam: From Head to Toe - John Stephenson
... Texture (bubble size) Adherence to glass (“lacing”) ...
... Texture (bubble size) Adherence to glass (“lacing”) ...
RalA ACTIVATION ASSAY BIOCHEM KIT
... The Ras family of small GTPases consists of at least 35 related human proteins that include the oncoproteins HRAS, KRAS and NRAS as the founding members (Colicelli 2004). The Ral proteins, RalA and RalB, share 58% identity to these oncoproteins and 85% identity with each other (Chardin and Tavitian ...
... The Ras family of small GTPases consists of at least 35 related human proteins that include the oncoproteins HRAS, KRAS and NRAS as the founding members (Colicelli 2004). The Ral proteins, RalA and RalB, share 58% identity to these oncoproteins and 85% identity with each other (Chardin and Tavitian ...
spectroscopic studies of mosquito iridescent virus, its capsid
... determined mainly by the individual properties of their π-electron systems, such as aromatic amino acids (tryptophan, tyrosine and phenylalanine), which are centers of intense UV absorption and fluorescence (λ > 200 nm). A success has been reached in modeling the spectra of large and complex native ...
... determined mainly by the individual properties of their π-electron systems, such as aromatic amino acids (tryptophan, tyrosine and phenylalanine), which are centers of intense UV absorption and fluorescence (λ > 200 nm). A success has been reached in modeling the spectra of large and complex native ...
products of the dioxygenase reaction ... useful intermediates for natural-product syntheses ...
... express in recombinant organisms, and until recently [30] no crystal structures have been available. Little practical engineering has been done with mammalian P450s; most mutagenesis studies have examined structure–function relationships [31]. Sakaki and Inouye [32] have discussed practical applicat ...
... express in recombinant organisms, and until recently [30] no crystal structures have been available. Little practical engineering has been done with mammalian P450s; most mutagenesis studies have examined structure–function relationships [31]. Sakaki and Inouye [32] have discussed practical applicat ...
Introduction to Carbohydrates
... A. Folic acid: a carrier of one-carbon units • The active form of folic acid, tetrahydrofolic acid (THF), is produced from folate by dihydrofolate reductase in a two-step reaction requiring two moles of NADPH. • The carbon unit carried by THF is bound to nitrogen N5 or N10, or to both N5 and N10. • ...
... A. Folic acid: a carrier of one-carbon units • The active form of folic acid, tetrahydrofolic acid (THF), is produced from folate by dihydrofolate reductase in a two-step reaction requiring two moles of NADPH. • The carbon unit carried by THF is bound to nitrogen N5 or N10, or to both N5 and N10. • ...
UNDERSTANDING PKU What is PKU? Phenylketonuria, or PKU
... Are people with PKU allergic to protein? No, people with PKU are not allergic to protein. Remember that there are 20 building blocks of protein. We need to get all 20 to keep our bodies working right. People with PKU still need protein, but can only tolerate small amounts of one of protein’s buildi ...
... Are people with PKU allergic to protein? No, people with PKU are not allergic to protein. Remember that there are 20 building blocks of protein. We need to get all 20 to keep our bodies working right. People with PKU still need protein, but can only tolerate small amounts of one of protein’s buildi ...
From transporter to transceptor
... have raised many questions as to why this specific amino acid transporter, which is only one of about 20 amino acid transporters in the yeast plasma membrane, needs such a complex regulation. Although studied in less detail, similar substrate-induced trafficking controls have been reported for multi ...
... have raised many questions as to why this specific amino acid transporter, which is only one of about 20 amino acid transporters in the yeast plasma membrane, needs such a complex regulation. Although studied in less detail, similar substrate-induced trafficking controls have been reported for multi ...
F-actin Sequesters Elongation Factor from Interaction with
... 1991). Interestingly, the other elongation factor (EF-2) has been demonstrated to bind directly to actin filaments (Bektas et al., 1994). Colocalization of these components with the cytoskeleton supports the speculation that protein synthesis in vivo is channeled, i.e., the components are organized ...
... 1991). Interestingly, the other elongation factor (EF-2) has been demonstrated to bind directly to actin filaments (Bektas et al., 1994). Colocalization of these components with the cytoskeleton supports the speculation that protein synthesis in vivo is channeled, i.e., the components are organized ...
Proteomic profiling of non-obese type 2 diabetic skeletal muscle
... The number of diabetic patients suffering from severe metabolic disturbances and glucotoxic complications is rapidly increasing worldwide and the incidence of diabetes is approaching endemic proportions (1). Type 2 diabetes mellitus represents a highly complex and heterogeneous disease that is influ ...
... The number of diabetic patients suffering from severe metabolic disturbances and glucotoxic complications is rapidly increasing worldwide and the incidence of diabetes is approaching endemic proportions (1). Type 2 diabetes mellitus represents a highly complex and heterogeneous disease that is influ ...
Gene Section MAPRE1 (Microtubule-associated protein, RP/EB family, member 1)
... binds to the APC C-terminus, so its binding is lost in most truncations. Also lost are other APC binding partners including the transcription factor beta-catenin. The role of APC as a tumor suppressor is thought to be through the beta-catenin pathway. Some evidence in the mouse suggests that this is ...
... binds to the APC C-terminus, so its binding is lost in most truncations. Also lost are other APC binding partners including the transcription factor beta-catenin. The role of APC as a tumor suppressor is thought to be through the beta-catenin pathway. Some evidence in the mouse suggests that this is ...
amino acid mixture
... explained if these amino acid residues were absorbed by an alternative peptide transport system which was not shared with glycylglycine. There are 400 possible dipeptides, so that our results cannot with certainty be extrapolated to the normal biological state. Moreover, if there is more than one pe ...
... explained if these amino acid residues were absorbed by an alternative peptide transport system which was not shared with glycylglycine. There are 400 possible dipeptides, so that our results cannot with certainty be extrapolated to the normal biological state. Moreover, if there is more than one pe ...
The Amino Acid Sequences of Cytochrome c from Four Plant Sources
... Proposed amino acid sequences of cytochrome c from nasturtium (Tropaeolum majus L.), box-elder (Acer negundo L.), elder (Sambucus nigra L.) and parsnip (Pastinaca sativa L.) are presented. Because of the very limited amounts of cytochrome available from some plant sources, peptides derived from the ...
... Proposed amino acid sequences of cytochrome c from nasturtium (Tropaeolum majus L.), box-elder (Acer negundo L.), elder (Sambucus nigra L.) and parsnip (Pastinaca sativa L.) are presented. Because of the very limited amounts of cytochrome available from some plant sources, peptides derived from the ...
Functional recognition of fragmented operator sites
... arc(Am) allele was re-introduced into the resultant P22 phage derivative by performing a mixed infection with the phage encoding the RNA hairpin and a replication-defective helper phage derivative containing the arc(Am) allele [P22mnt::Kn9Omnt ::SmaI–EcoRIarcH1605(Am)ant::lacZ] in MS1883. Phage lysa ...
... arc(Am) allele was re-introduced into the resultant P22 phage derivative by performing a mixed infection with the phage encoding the RNA hairpin and a replication-defective helper phage derivative containing the arc(Am) allele [P22mnt::Kn9Omnt ::SmaI–EcoRIarcH1605(Am)ant::lacZ] in MS1883. Phage lysa ...
Exploring Prostate Proteins and Antibodies
... Which proteins are expressed in the prostate? To acknowledge Prostate Cancer Awareness Month, we take a closer look at the human prostate specific proteome. We explore the Human Protein Atlas's analysis of the prostate specific transcriptome, and present selected antibodies against proteins specific ...
... Which proteins are expressed in the prostate? To acknowledge Prostate Cancer Awareness Month, we take a closer look at the human prostate specific proteome. We explore the Human Protein Atlas's analysis of the prostate specific transcriptome, and present selected antibodies against proteins specific ...
The Emerging Age of Cell-free Synthetic Biology
... expression is introduced by each of the individual gene parts, such as promoters, ribosome binding sites, gene sequence, and vector origin of replications; all of which can impact expression levels in ambiguous manners [14]. Optimizing synthetic pathways is further complicated by idiosyncratic and o ...
... expression is introduced by each of the individual gene parts, such as promoters, ribosome binding sites, gene sequence, and vector origin of replications; all of which can impact expression levels in ambiguous manners [14]. Optimizing synthetic pathways is further complicated by idiosyncratic and o ...
Full Text
... possible groups. Choosing among these possibilities with statistical validity requires extremely large training sets. But in practice, training sets usually contain fewer than 100 sequences, so motifs generated this way are highly underdetermined. On the other hand, some methods restrict the allowed ...
... possible groups. Choosing among these possibilities with statistical validity requires extremely large training sets. But in practice, training sets usually contain fewer than 100 sequences, so motifs generated this way are highly underdetermined. On the other hand, some methods restrict the allowed ...
Protein

Proteins (/ˈproʊˌtiːnz/ or /ˈproʊti.ɨnz/) are large biomolecules, or macromolecules, consisting of one or more long chains of amino acid residues. Proteins perform a vast array of functions within living organisms, including catalyzing metabolic reactions, DNA replication, responding to stimuli, and transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the nucleotide sequence of their genes, and which usually results in protein folding into a specific three-dimensional structure that determines its activity.A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than about 20-30 residues, are rarely considered to be proteins and are commonly called peptides, or sometimes oligopeptides. The individual amino acid residues are bonded together by peptide bonds and adjacent amino acid residues. The sequence of amino acid residues in a protein is defined by the sequence of a gene, which is encoded in the genetic code. In general, the genetic code specifies 20 standard amino acids; however, in certain organisms the genetic code can include selenocysteine and—in certain archaea—pyrrolysine. Shortly after or even during synthesis, the residues in a protein are often chemically modified by posttranslational modification, which alters the physical and chemical properties, folding, stability, activity, and ultimately, the function of the proteins. Sometimes proteins have non-peptide groups attached, which can be called prosthetic groups or cofactors. Proteins can also work together to achieve a particular function, and they often associate to form stable protein complexes.Once formed, proteins only exist for a certain period of time and are then degraded and recycled by the cell's machinery through the process of protein turnover. A protein's lifespan is measured in terms of its half-life and covers a wide range. They can exist for minutes or years with an average lifespan of 1–2 days in mammalian cells. Abnormal and or misfolded proteins are degraded more rapidly either due to being targeted for destruction or due to being unstable.Like other biological macromolecules such as polysaccharides and nucleic acids, proteins are essential parts of organisms and participate in virtually every process within cells. Many proteins are enzymes that catalyze biochemical reactions and are vital to metabolism. Proteins also have structural or mechanical functions, such as actin and myosin in muscle and the proteins in the cytoskeleton, which form a system of scaffolding that maintains cell shape. Other proteins are important in cell signaling, immune responses, cell adhesion, and the cell cycle. Proteins are also necessary in animals' diets, since animals cannot synthesize all the amino acids they need and must obtain essential amino acids from food. Through the process of digestion, animals break down ingested protein into free amino acids that are then used in metabolism.Proteins may be purified from other cellular components using a variety of techniques such as ultracentrifugation, precipitation, electrophoresis, and chromatography; the advent of genetic engineering has made possible a number of methods to facilitate purification. Methods commonly used to study protein structure and function include immunohistochemistry, site-directed mutagenesis, X-ray crystallography, nuclear magnetic resonance and mass spectrometry.