0210195725
0210195780
0210195790
0210195791
ICNA0210195725EA
30.2
EUR
InStock
ICNA0210195725
ICNA0210195780
ICNA0210195790
ICNA0210195791
L(+)-Histidine monochlorhydrate monohydraté, poudre blanche
L(+)-Histidine monochlorhydrate monohydraté
L-Histidine has been used to study cultures of the human T-lymphoblastic leukemia cell line MOLT-4 to study modulation of apoptosis. Exogenous histidine has been shown to enhance the biosynthesis of lovastatin by cultured Aspergillus terreus. Histidine has been utilised as a single nitrogen source to probe swarming in Pseudomonas aeruginosa on agar. An in vivo study has used L-histidine to diminish the net secretory response of the small intestine of of cholera toxin-challenged mice.
Because the pKa of the imidazole group is close to physiological pH, the imidazole moiety can be either uncharged or positively charged, depending on the local environment. This property makes histidine residues of exceptional interest in the active sites of many proteins, such as hemoglobin and myoglobin, where the imidazole ring can readily alternate between the charged (imidazolium) and uncharged (imidazole) states to participate in bond formation and breakage. Histidine is biosynthesised from ATP, 5-phosphoribosyl-1-pyrophosphate (PRPP), and glutamine. In turn, histidine is degraded to glutamate by histidase, urocanase, and imidazolonepropionase via the formation of urocanate, 4-imidazolone 5-propionate, and N-formiminoglutamate.
Soluble in water (50 mg/ml); insoluble in diethyl ether, methanol and alcohol.
Attention: Research Use Only (RUO).