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  • protein
  • Since the distance between the two helix-turn-helix motifs is too great to allow binding to two adjacent major grooves of the 16-bp Mor-binding site, it is likely that conformational changes in both the protein and DNA will be required for Mor to interact with the DNA (Fig. 3). (uthsc.edu)
  • Mycoplasma genitalium, Mycobacterium tuberculosis), while Pyrococcus horikoshii has both a full length MetG and a second protein homologous to the beta chain only. (ebi.ac.uk)
  • LeuT acts as a symporter, an integral membrane protein that works as a cotransporter linking the passage of two sodium ions across the membrane with the transport of the amino acid in the same direction thus making the process energetically favorable. (wikipedia.org)
  • The method is based on analyses of the relative frequencies of each amino acid in alpha helices, beta sheets, and turns based on known protein structures solved with X-ray crystallography. (wikipedia.org)
  • The original Chou-Fasman parameters were derived from a very small and non-representative sample of protein structures due to the small number of such structures that were known at the time of their original work. (wikipedia.org)
  • He later joined other researchers (notably the American chemist Maurice Huggins) in proposing that: the unstretched protein molecules formed a helix (which he called the α-form) the stretching caused the helix to uncoil, forming an extended state (which he called the β-form). (wikipedia.org)
  • The most common location of α helices is at the surface of protein cores, where they provide an interface with the aqueous environment. (wikipedia.org)
  • proteins
  • In E. coli, the lipid II transporter candidate FtsW is thought to work in concert with the PG synthases penicillin-binding proteins PBP3 and PBP1b. (ac.be)
  • To investigate contribution of individual side chains into membrane binding we have used Alanine and other substitutions in the Gt-gamma(60-71) region and examined the effects of the replacements on the ability of the mutant proteins to interact with lipid membranes. (arvojournals.org)
  • The mutant Gt-gamma proteins have been co-expressed with histidine labeled Gt-beta subunits in SF9 insect cells to form functionally active dimers, as determined by their ability to interact with R* after reconstitution with purified Gt-alpha. (arvojournals.org)
  • Among types of local structure in proteins, the α-helix is the most regular and the most predictable from sequence, as well as the most prevalent. (wikipedia.org)
  • In 1954, Pauling was awarded his first Nobel Prize "for his research into the nature of the chemical bond and its application to the elucidation of the structure of complex substances" (such as proteins), prominently including the structure of the α-helix. (wikipedia.org)
  • amino acid
  • Two sets of alpha helices are thought to perform the rocking action by directly changing its shape after the binding of the amino acid to the structure. (wikipedia.org)
  • The Gt-gamma(60-71) helix appears to run in parallel to the plane of the membrane and it may contain membrane binding elements in addition to the amino acid side chains involved in R*-binding. (arvojournals.org)
  • molecules
  • In addition to traditional beta-lactams, other classes of molecules (non-beta-lactams) that inhibit PBPs are now emerging, opening new perspectives for tackling the resistance problem while taking advantage of these valuable targets, for which a wealth of structural and functional knowledge has been accumulated. (ac.be)
  • hydrogen
  • this repeated i + 4 → i hydrogen bonding is the most prominent characteristic of an α-helix. (wikipedia.org)
  • Official international nomenclature specifies two ways of defining α-helices, rule 6.2 in terms of repeating φ, ψ torsion angles (see below) and rule 6.3 in terms of the combined pattern of pitch and hydrogen bonding. (wikipedia.org)
  • molecular
  • It was first crystallized to understand the inner molecular mechanisms of antidepressant's work since it has a close resemblance with the human neurotransmitter transporters (more difficult to crystallize) that these drugs block, thus inhibiting the reuptake of chemical messengers across the cell membrane of nerve axons and glial cells. (wikipedia.org)
  • helical
  • However, tRNA binding involves an alpha-helical structure that is conserved between class I and class II synthetases. (ebi.ac.uk)
  • fold
  • Class II aminoacyl-tRNA synthetases share an anti-parallel beta-sheet fold flanked by alpha-helices [ PMID: 8364025 ], and are mostly dimeric or multimeric, containing at least three conserved regions [ PMID: 8274143 , PMID: 2053131 , PMID: 1852601 ]. (ebi.ac.uk)
  • The N-terminus is a Rossmann NAD-binding fold and the C-terminus is an unusual alpha+beta fold. (wikipedia.org)
  • regions
  • Turns are also evaluated in four-residue windows, but are calculated using a multi-step procedure because many turn regions contain amino acids that could also appear in helix or sheet regions. (wikipedia.org)
  • form
  • that paper showed both right- and left-handed helices, although in 1960 the crystal structure of myoglobin showed that the right-handed form is the common one. (wikipedia.org)
  • interactions
  • From order of addition experiments, it appears that both C and Mor are able to recruit RNAP to the promoter, using alpha-CTD/UP-element, sigma/-10 element, and RNAP-activator interactions. (uthsc.edu)
  • These interactions works on a basis of preference dependent on energy properties and specificity. (wikipedia.org)
  • structural
  • The group worked on a variety of structural problems until joining the NIST/UMBI Center for Advanced Research in Biotechnology (CARB) in 1987. (thefreelibrary.com)
  • residue
  • Approximate phi and psi angles for the second residue in a type-II beta turn are -60º and +120º. (vital-it.ch)
  • tRNA
  • The aminoacyl-tRNA synthetase family: modules at work. (ebi.ac.uk)
  • This family describes a region of the methionyl-tRNA synthetase that is present at the C terminus of MetG in some species (Escherichia coli, Bacillus subtilis, Thermotoga maritima, Methanothermobacter thermautotrophicus (Methanobacterium thermoformicicum), and as a separate beta chain in Aquifex aeolicus [ PMID: 10369686 , PMID: 12481025 ]. (ebi.ac.uk)
  • turn
  • A turn is predicted only if the turn probability is greater than the helix or sheet probabilities and a probability value based on the positions of particular amino acids in the turn exceeds a predetermined threshold. (wikipedia.org)
  • If p(t) exceeds an arbitrary cutoff value (originally 7.5e-3), the mean of the p(j)'s exceeds 1, and p(t) exceeds the alpha helix and beta sheet probabilities for that window, then a turn is predicted. (wikipedia.org)
  • After the beta turn, the second part of the chain turns back to run parallel (antiparallel, actually) to the first portion. (vital-it.ch)
  • The structure of the chain domain is 4-turn alpha helix structure. (wikipedia.org)
  • chain
  • The noticeable difference between the two subunits that make up LDH's tertiary structure is the replacement of alanine (in the M chain) with a glutamine (in the H chain). (wikipedia.org)
  • The initial evidence for a ball and chain inactivation came in 1977 with Clay Armstrong and Francisco Bezanilla's work. (wikipedia.org)
  • present
  • In this paper, we present a general background on the GTs and TPs/PBPs, a survey of recent issues of bacterial resistance and a review of recent works describing new inhibitors of these enzymes. (ac.be)
  • theme
  • Dunitz describes how Pauling's first article on the theme in fact shows a left-handed helix, the enantiomer of the true structure. (wikipedia.org)
  • either
  • While olefin binding to either the endo or exo face of the helix is sterically allowed, only endo binding orients the NH-4 group to bind with the hydroperoxide moiety allowing for hydroxide displacement in the final reaction step (Figure 4). (wikipedia.org)
  • shown
  • In vitro transcription experiments with reconstituted mutant RNAPs showed that both the alpha-CTD and sigma-CTD are required for Mor-dependent activation of the middle promoter, leading to our working hypothesis for activation shown in Figure 1. (uthsc.edu)
  • models
  • Neurath's paper and Astbury's data inspired H. S. Taylor, Maurice Huggins and Bragg and collaborators to propose models of keratin that somewhat resemble the modern α-helix. (wikipedia.org)
  • original work
  • This is an open access article distributed under the Creative Commons Attribution License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (hindawi.com)
  • sheet
  • As originally described, four out of any six contiguous amino acids were sufficient to nucleate helix, and three out of any contiguous five were sufficient for a sheet. (wikipedia.org)
  • If the first two conditions are met but the probability of a beta sheet p(b) exceeds p(t), then a sheet is predicted instead. (wikipedia.org)
  • levels
  • Furthermore, the reaction has been effectively scaled up to industrially useful levels, with work conducted notably by Bayer and Evonik. (wikipedia.org)