Bis[3-chloro-6-(3,5-dimethyl-1H-pyrazol-1-yl)picolinato]nickel(II) tetrahydrate
In the title complex, [Ni(C11H9ClN3O2)2]·4H2O, the Ni atom is coordinated by four N atoms and two O atoms derived from two tridentate 3-chloro-6-(3,5-dimethyl-1H-pyrazol-1-yl)picolinate ligands. The cis-N4O2 donor set defines a distorted octahedral geometry. In the crystal structure, the complex and water molecules are linked by O—H⋯O hydrogen bonds.
Bis[6-(3,5-dimethyl-1 H -pyrazol-1-yl-κ N 2 )picolinato-κ 2 N , O ]zinc(II) trihydrate
In the title compound, [Zn(C11H10N3O2)2]·3H2O, the ZnII atom is coordinated by four N and two O atoms in a distorted octa­hedral geometry. One water molecule is disordered equally over two positions.
Comparative studies of α-Lactalbumin and lysozyme: Echidna lysozyme
Summaryα-Lactalbumin is a modifier protein for galactosyl transferase in the biosynthesis of lactose and lysozyme catalyses the cleavage of β(1–4) glycosidic linkages. It is now generally believed that α-lactalbumin and lysozyme have diverged from a common ancestor. Comparative studies of these proteins from several species are reported here.The presence of lactose and lactose synthetase activity is shown in mature milk samples from a variety of placental mammals (eutheria) and a pouch bearing mammal (marsupialia). The isolation of the α-lactalbumins involved and their properties are compared.The position is different in the milk samples of monotremes. The α-lactalbumin, lactose and lactose synthetase activity levels in the two platypus samples studied are very low. The levels of lactose and lactose synthetase activity in some echidna(Tachyglossus aculeatus) samples are low, but appreciable in others. No α-lactalbumin is present. The lysozyme activity is appreciable, some samples containing a different lysozyme from that present in others. One of these (designated echidna lysozyme I) is capable of lactose synthetase modifier activity in the presence of bovine “A protein”.The properties of this lysozyme are compared with those of lysozymes and α-lactalbumins from a variety of species and their significance is discussed.