Histidine His

It is a peptide containing 27 amino acid residues containing the amino acids L-histidine (His) L-aspartic acid (Asp) L-serine (Ser) glycine (Gly) L-threonine (Thr) L-phenyl-alanine (Phe) L-glutamic acid (Glu) L-glutamine [Glu(NHj)] L-leucine (Leu) L-arginine (Arg) L-alanine (Ala) and L-valinamide (Va -NHj). 

Figure 4.8 Reduction of Na/K ATPase activity in isoiated guinea-pig hearts subjected to ischaemia/reperfusion and its prevention by various agents control non-ischaemic hearts (Nl) guinea-pig hearts subjected to global ischaemia for 2 h and subsequently reperfused for 1 h (IR). In other preparations, superoxide dismutase (SOD) 100 U/ml, catalase (CAT) 150 U/ml, dimethylsulphoxide (DMS) 50 mu, histidine (HIS) 10 mu, vitamin E (TOC)...

We used recombinant DNA technology to design unique substrates for in vitro expansion of rat NSCs. For example, we fused a small peptide sequence of six consecutive histidine (His) residues to the C-terminus of human EGF (EGF-His). This EGF-His was anchored to the surface of a glass-based substrate by coordination with Ni2+ ions, which were fixed on the surface of a SAM of alkanethiol. Strikingly, neither a covalently immobilized EGF-His nor a physically adsorbed... 

A catalytically inactive, (tyrosinato)Cu(II)-containing form of GO (pH 4.5 acetate buffer) has been characterized by X-ray crystallography (119, 120) at 1.7-A resolution. Fig. 6 shows the active site. The Cu(II) ion is in a distorted square-based pyramidal environment of a tyrosine (Tyr 495) ligand in the apical position where it is probably bound in its protonated phenol form, a second (modified) tyrosinate (Tyr 272) as well as two histidines (His 496, His 581) in equatorial positions. The fifth coordination site is occupied by a buffer derived acetate that in the active en-... 

Histidine His H 2-Amino-3-(l//-imidazol-4-yl)propanoic acid CHi- C - COOH... 

Typical buffers are 20 mM 2-(N-morpholino)ethanesulfonic acid (MES) and 20 mM histidine (His) for the direct conductivity detection of both inorganic cations and inorganic anions. An alkaline sorbate/arginine (7.5/15 mM) buffer is suitable for direct conductivity... 

Finally, they may be classified on the basis of whether they are nonessential, essential (exogenous), and conditionally essential amino acids. Food and tissue proteins contain 20 amino acids of nutritional importance. Nine of these amino acids (histidine (His), He, Leu, Lys, methionine (Met), Phe, Thr, Trp, and Val) cannot be synthesized by the body and they are therefore essential or indispensable nutrients that must be... 

The crystal structure (Strop et al. 2001) reveals a homodimer with the zinc atom ligated by the sulfur atoms of two cysteines (Cys 32 and Cys 90) and the nitrogen atom of a histidine (His 87), as is the case for the plant-type enzyme (Fig. 11.3). The active site contains an HEPES buffer molecule in a position that implicates involvement of Asp 34 in the transport of protons after ionization of the zinc-bound water. 

The flipped orientation of the heme in HPII and PVC results in the oxidized ring being sufficiently well removed (7 A) from the essential histidine (His 128 in HPII) and the presumed peroxide binding site to complicate an explanation of the reaction mechanism. The explanation is further complicated by the cis-stereospecificity of the reaction that results in both oxygens being situated on the proximal side of the heme away from what is considered to be the normal reaction center on the distal side. This stereochemistry dictates that the hydroxyl group on the heme d have originated on the proximal side of the heme, and a mechanism has been proposed to explain the reaction in both PVC and HPII 93). The mechanism assumes that compound I is formed as a first step... 

Name and abbreviation, formed from the first three letters of the name (e.g., histidine, His)... 

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