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Zhongliang Zhu

Publications and source records attributed to Zhongliang Zhu.

9 recordsLinked to original sources
PubMed2006

Synthesis, structural characterization, and spectroscopy of the cadmium-cadmium bonded molecular species Ar'CdCdAr' (Ar' = C6H3-2,6-(C6H3-2,6-Pri2)2).

The synthesis and first structural characterization of a cadmium-cadmium bonded molecular compound Ar'CdCdAr' (Ar' = C6H3-2,6-(C6H3-2,6-Pri2)2) are reported. The existence of the Cd-Cd bond was established by 113Cd NMR spectroscopy and X-ray diffraction (Cd-Cd = 2.6257(5) A). Like its group 12 analogue Ar'ZnZnAr', DFT calculations showed that Ar'CdCdAr' had significant p-character in the Cd-Cd sigma-bonding HOMO.

Journal Article↗
PubMed2006

Prenatal stress on the kinetic properties of Ca2+ and K+ channels in offspring hippocampal CA3 pyramidal neurons.

Prenatal stress is known to cause neuronal loss and oxidative damage in the hippocampus of offspring rats. To further understand the mechanisms, the present study was undertaken to investigate the effects of prenatal stress on the kinetic properties of high-voltage-activated (HVA) Ca(2+) and K(+) channels in freshly isolated hippocampal CA3 pyramidal neurons of offspring rats. Pregnant rats in the prenatal stress group were exposed to restraint stress on days 14-20 of pregnancy three times daily for 45 min. The patch clamp technique was employed to record HVA Ca(2+) and K(+) channel currents. Prenatal stress significantly increased HVA Ca(2+) channel disturbance including the maximal average HVA calcium peak current amplitude (-576.52+/-7.03 pA in control group and -702.05+/-6.82 pA in prenatal stress group, p<0.01), the maximal average HVA Ca(2+) current density (-40.89+/-0.31 pA/pF in control group and -49.44+/-0.37 pA/pF in prenatal stress group, p<0.01), and the maximal average integral current of the HVA Ca(2+) channel (106.81+/-4.20 nA ms in control group and 133.49+/-4.59 nA ms in prenatal stress group, p<0.01). The current-voltage relationship and conductance--voltage relationship of HVA Ca(2+) channels and potassium channels in offspring CA3 neurons were not affected by prenatal stress. These data suggest that exposure of animals to stressful experience during pregnancy can exert effects on calcium ion channels of offspring hippocampal neurons and that the calcium channel disturbance may play a role in prenatal stress-induced neuronal loss and oxidative damage in offspring brain.

Animals↗
PubMed2005

Crystal structure of human vacuolar protein sorting protein 29 reveals a phosphodiesterase/nuclease-like fold and two protein-protein interaction sites.

Vacuolar protein sorting protein 29 (Vps29p), which is involved in retrograde trafficking from prevacuolar endosomes to the trans-Golgi network, performs its biological functions by participating in the formation of a "retromer complex." In human cells, this complex comprises four conserved proteins: hVps35p, hVps29p, hVps26p, and sorting nexin 1 protein (SNX1). Here, we report the crystal structure of hVps29p at 2.1 Angstroms resolution, the first three-dimensional structure of the retromer subunits. This novel structure adopts a four-layered alpha-beta-beta-alpha sandwich fold. hVps29p contains a metal-binding site that is very similar to the active sites of some proteins of the phosphodiesterase/nuclease protein family, indicating that hVps29p may carry out chemically similar functions. Structure and sequence conservation analysis suggests that hVps29p contains two protein-protein interaction sites. One site, which potentially serves as the interface between hVps29p and hVps35p, comprises 5 conserved hydrophobic and 8 hydrophilic residues. The other site is relatively more hydrophilic and may serve as a binding interface with hVps26p, SNX1, or other target proteins.

Amino Acid Sequence↗
PubMed2005

Crystal structures and amidolytic activities of two glycosylated snake venom serine proteinases.

We deduced that Agkistrodon actus venom serine proteinases I and II, previously isolated from the venom of A. acutus (Zhu, Z., Gong, P., Teng, M., and Niu, L. (2003) Acta Crystallogr. Sect. D Biol. Crystallogr. 59, 547-550), are encoded by two almost identical genes, with only the single substitution Asp for Asn at residue 62. Amidolytic assays indicated that they possess slightly different enzymatic properties. Crystal structures of A. actus venom serine proteinases I and II were determined at resolution of 2.0 and 2.1 A with the identification of trisaccharide (NAG(301)-FUC(302)-NAG(303)) and monosaccharide (NAG(301)) residues in them, respectively. The substrate binding sites S3 of the two proteinases appear much shallower than that of Trimeresurus stejnegeri venom plasminogen activator despite the overall structural similarity. Based on structural analysis, we showed that these Asn(35)-linked oligosaccharides collide spatially with some inhibitors, such as soybean trypsin inhibitor, and would therefore hinder their inhibitory binding. Difference of the carbohydrates in both the proteinases might also lead to their altered catalytic activities.

Agkistrodon↗
PubMed2004

Prenatal stress causes gender-dependent neuronal loss and oxidative stress in rat hippocampus.

Our purpose was to investigate the effects of prenatal stress on neuronal changes in the hippocampus and the possible involvement of oxidative stress in female and male rats. Female and male offspring (1-month-old), whose dams were restrained in middle or later pregnant stage (MS or LS), were studied to observe changes in the number of hippocampal neurons and the expression of neuronal nitric oxide synthase (nNOS) in the hippocampus. Both MS and LS induced an increase in the number of nNOS-positive expression in female and male offspring in the hippocampus; however, both MS and LS caused a significant decrease in the number of hippocampal neurons in the female, but not in the male offspring. In addition, significant increases in calcium content and oxidant generation were induced by LS in the hippocampal CA3 region in female rats. These data suggest that prenatal stress can cause oxidative stress and consequent damage to neurons, leading to neuronal loss in the brain of offspring during development.

Animals↗
PubMed2003

Purification, N-terminal sequencing, partial characterization, crystallization and preliminary crystallographic analysis of two glycosylated serine proteinases from Agkistrodon acutus venom.

AaV-SP-I and AaV-SP-II, two glycosylated serine proteinases from Agkistrodon acutus venom with fibrinogenolysis and esterolysis activities, have been purified to homogeneity by three-step ion-exchange chromatography. Estimated by SDS-PAGE, the molecular weights of AaV-SP-I and AaV-SP-II are about 32 and 31 kDa under reducing conditions and 26 and 25 kDa under non-reducing conditions, respectively. The first 24 N-terminal amino-acid residues are the same in both sequences and display a high homology with those of several snake-venom serine proteinases. However, the proteins possess obviously distinct carbohydrate contents. Using the conventional hanging-drop vapour-diffusion method, single crystals of both enzymes were grown that were suitable for X-ray diffraction analysis. The crystals of AaV-SP-I and AaV-SP-II belong to space groups P2(1)2(1)2(1) and C2, respectively. In each case there is only one molecule in the asymmetric unit.

Agkistrodon↗
PubMed2002

Purification, crystallization and preliminary X-ray crystallographic analysis of agkaggregin, a C-type lectin-like protein from Agkistrodon acutus venom.

A snake-venom C-type lectin-like protein, agkaggregin, has been isolated from Agkistrodon acutus venom. Agkaggregin has an apparent molecular mass of about 28 kDa and consists of two different types of subunits, an alpha-subunit (approximately 15 kDa) and a beta-subunit (approximately 14 kDa). Agkaggregin has the ability to induce platelet aggregation at concentrations of the order of nanomoles. The agkaggregin crystals grew for nearly a year by hanging-drop vapour diffusion and belong to the I222 space group, with unit-cell parameters a = 64.75, b = 74.21, c = 133.24 A. One asymmetric unit contains one alphabeta heterodimer, corresponding to a volume-to-mass ratio of 2.795 A(3) Da(-1). Agkaggregin may exist in two association forms: an alphabeta heterodimer and a dimer of alphabeta heterodimers that associates during the long process of crystallization.

Crotalid Venoms↗