Abstract:
:Multiply branched polylactosaminoglycans are expressed in glycoproteins and glycolipids of many cells. Interest in their biology stems from their abundant expression in early embryonal cells and from their ability to carry multiple lectin-binding determinants, which makes them prominent ligands and antagonists of cell adhesion proteins. A prototype of their backbones is represented by the decasaccharide LacNAc beta1-3'(LacNAc beta1-6')LacNAc beta1-3'(LacNAc beta1-6')LacNAc (5), where LacNAc is the disaccharide Gal beta1-4GlcNAc. Here, we describe in vitro biosynthesis of glycan 5. Incubation of the linear hexasaccharide LacNAc beta1-3'LacNAc beta1-3'LacNAc (1) with UDP-GlcNAc and alpha midchain beta1,6-GlcNAc transferase activity (GlcNAc to Gal), present in rat serum [Gu, J., Nishikawa, A., Fujii, S., Gasa, S., & Taniguchi, N. (1992) J. Biol. Chem. 267, 2994-2999], gave the doubly branched octasaccharide LacNAc beta1-3'(GlcNAc beta1-6')LacNAc beta1-3'(GlcNAc beta1-6')LacNAc (4). The latter was converted to 5 by enzymatic beta1,4-galactosylation. In the initial branching reaction of 1, two isomeric heptasaccharide intermediates, LacNAc beta1-3'LacNAc beta1-3'(GlcNAc beta1-6')LacNAc (2) and LacNAc beta1-3'(GlcNAc beta1-6')LacNAc beta1-3'LacNAc (3), were formed first at comparable rates. Later, both intermediates were converted to 4, revealing two distinct pathways of the reaction: 1 --> 2 --> 4 and 1 --> 3 --> 4. These data suggest that, regardless of their chain length, linear polylactosamines similar to 1 contain potential branching sites at each of the internal galactoses. The enzyme-binding epitope of 1 is probably LacNAc beta1-3'LacNAc, because the trisaccharides GlcNAc beta1-3'LacNAc and LacNAc beta1-3Gal as well as the tetrasaccharide GlcNAc beta1-3'LacNAc beta1-3Gal were poor acceptors, while LacNAc beta1-3'LacNAc was a good one. Midchain beta1,6-GlcNAc transferase activities present in serum of several mammalian species, including man, resembled closely the rat serum activity in their mode of action and in their acceptor specificity. We suggest that analogous membrane-bound Golgi enzymes are involved in the biosynthesis of multiply branched polylactosamines in vivo.
journal_name
Biochemistryjournal_title
Biochemistryauthors
Leppanen A,Salminen H,Zhu Y,Maaheimo H,Helin J,Costello CE,Renkonen Odoi
10.1021/bi9627673subject
Has Abstractpub_date
1997-06-10 00:00:00pages
7026-36issue
23eissn
0006-2960issn
1520-4995pii
bi9627673journal_volume
36pub_type
杂志文章相关文献
BIOCHEMISTRY文献大全abstract::We have employed molecular dynamics (MD) simulation to investigate, with atomic details, the structural dynamics and energetics of three major ATPase states (ADP, APO, and ATP state) of a human kinesin-1 monomer in complex with a tubulin dimer. Starting from a recently solved crystal structure of ATP-like kinesin-tubu...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi501056h
更新日期:2015-01-27 00:00:00
abstract::The aspartate receptors of Escherichia coli and Salmonella typhimurium which mediate chemotactic responsiveness to aspartate have 79% amino acid sequence identity but exhibited apparently quite different aspartate binding plots. The Scatchard plot of the Salmonella receptor was concave upward whereas the E. coli recep...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00169a002
更新日期:1994-01-25 00:00:00
abstract::To determine the active site cysteine residue in aldehyde dehydrogenase, we mutated amino acid residues 49, 162, and 302 of recombinantly expressed rat liver mitochondrial (class 2) aldehyde dehydrogenase. The C49A and C162A mutants were fully active tetrameric enzymes, although the C162A mutant was found to be highly...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00008a025
更新日期:1995-02-28 00:00:00
abstract::The subgel phases of a homologous series of saturated straight-chain diacylphosphatidylcholines with hydrocarbon chains consisting of 10-18 carbon atoms were studied by Fourier-transform infrared spectroscopy. All of these lipids initially form a subgel phase which is spectroscopically similar to that obtained when fu...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00486a024
更新日期:1990-08-28 00:00:00
abstract::Human protein Z is a vitamin K-dependent plasma glycoprotein, deficiency of which leads to a mild bleeding tendency. Protein Z appears to assist hemostasis by binding thrombin and promoting its association with phospholipid vesicles. In this study, to characterize the gene for protein Z, its organization and structure...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi972002a
更新日期:1998-05-12 00:00:00
abstract::A specific, high-affinity binding site for ammodytoxin C in synaptic membranes from bovine cerebral cortex was detected and partially characterized. Equilibrium binding analysis revealed a single population of [125I]ammodytoxin C acceptors with the following binding parameters: Kd = 6.0 nM and Bmax = 5.7 pmol/mg membr...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00250a049
更新日期:1994-11-22 00:00:00
abstract::Nonenzymatic deamidation of asparagine and glutamine in peptides and proteins is a frequent modification both in vivo and in vitro. The biological effect is not completely understood, but it is often associated with protein degradation and loss of biological function. Here we describe the deamidation of CsgA, the majo...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.7b00241
更新日期:2017-06-13 00:00:00
abstract::The major phospholipids, phosphatidylcholine and spingomyelin, of low density lipoprotein (LDL) are accessible to small amounts of Pr3+, suggesting that the head groups of all mobile phospholipids are on the surface of the particle in contact with the aqueous medium. The major source of the nuclear Overhauser effect e...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00607a002
更新日期:1978-07-11 00:00:00
abstract::The bacterial second messenger signaling molecule bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) controls important biological processes such as biofilm formation, virulence response, and motility. This second messenger is sensed by macromolecular targets inside the cell, both protein and RNA, which ind...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi301510v
更新日期:2013-01-15 00:00:00
abstract::Specific enzymatic and chemical degradation of neutral lipid and phospholipid fractions from rat liver revealed the presence of novel types of lipid metabolites bearing a short-chain diol backbone. Diol-derived lecithin and cephalin analogs were readily cleaved by phospholipase C (EC 3.1.4.3) from Bacillus cereus, alt...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00675a031
更新日期:1975-02-25 00:00:00
abstract::A 15-residue fragment within the major continuous domain of gp120 from HIV-1 that can bind independently to the CD4 receptor has been shown to have the property of behaving as a solvent polarity-dependent conformational switch. The switch behavior (cooperative transition from beta-sheet to helical conformation as a fu...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi952045w
更新日期:1996-01-16 00:00:00
abstract::Oxalate:ferredoxin oxidoreductase (OOR) is an unusual member of the thiamine pyrophosphate (TPP)-dependent 2-oxoacid:ferredoxin oxidoreductase (OFOR) family in that it catalyzes the coenzyme A (CoA)-independent conversion of oxalate into 2 equivalents of carbon dioxide. This reaction is surprising because binding of C...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/acs.biochem.7b00222
更新日期:2017-06-06 00:00:00
abstract::Recently, we synthesized the first individual β,γ-CHX-dGTP diastereomers [(R)- or (S)-CHX, where X is F or Cl] and determined their structures in ternary complexes with DNA polymerase β (pol β). We now report stereospecificity by pol β on the mixed β,γ-CHX diastereomer pairs using nuclear magnetic resonance and on the...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi3010335
更新日期:2012-10-30 00:00:00
abstract::Human ecto-ATPase (E-NTPDase 2) and chicken ecto-ATP-diphosphohydrolase (E-NTPDase 8) are cell surface nucleotidases with two transmembranous domains, one each at the N- and C-termini. Hydrolysis of substrates occurs in active sites residing in their extracellular domains. Human ecto-ATPase activity is decreased by NP...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi050019k
更新日期:2005-08-23 00:00:00
abstract::Oligopeptides and dipeptides are transported into Saccharomyces cerevisiae by a carrier-mediated system. In the dark, leucyl-p-nitroanilide (Leu-p-NA) and leucyl-leucyl-4-azido-2-nitrophenylalanine [Leu-Leu-Phe-(4N3,2NO2)] are competitive inhibitors of peptide transport by S. cerevisiae cells. The photolysis of yeast ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00266a037
更新日期:1982-11-09 00:00:00
abstract::FTIR-difference spectroscopy in combination with site-directed mutagenesis has been used to investigate the role of water during the photocycle of bacteriorhodopsin. At least one water molecule is detected which undergoes an increase in H-bonding during the primary bR-->K phototransition. Bands due to water appear in ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00209a005
更新日期:1994-11-01 00:00:00
abstract::Adenosine A(2B) receptors, which play a role in inflammation and cancer, are of considerable interest as novel drug targets. To gain deeper insights into ligand binding and receptor activation, we exchanged amino acids predicted to be close to the binding pocket. The alanine mutants were stably expressed in CHO cells ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi3012065
更新日期:2013-01-29 00:00:00
abstract::Inherently curved DNA segments, associated with short runs of adenines, have been identified in many gene regulatory regions, yet their physiological significance remains unknown. The observations reported in this study indicate that intrinsically bent nucleic acid fragments are characterized by substantially attenuat...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00123a019
更新日期:1992-03-03 00:00:00
abstract::An issue that is central to understanding cellular fatty acid (FA) metabolism is whether physiologic transport of FA across cell membranes requires protein mediation or can be satisfied by the rate of spontaneous movement through the lipid phase. For this reason, considerable effort has been devoted to determining the...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi962007s
更新日期:1997-05-13 00:00:00
abstract::The two distinct domains of flavocytochrome b2 (L-lactate:cytochrome c oxidoreductase, EC 1.1.2.3) are connected by a typical hinge peptide. To probe the importance of the structural integrity of the hinge region for efficient intraprotein electron transfer, three mutant enzymes have been constructed: H delta 3 [Sharp...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi950457z
更新日期:1996-01-23 00:00:00
abstract::Azotobacter vinelandii bacterioferritin (AvBF) containing 800-1500 Co or Mn atoms as Co(III) and Mn(III) oxyhydroxide cores (Co-AvBF, Mn-AvBF) was synthesized by the same procedure used previously for horse spleen ferritin (HoSF). The kinetics of reduction of Co-AvBF and Mn-AvBF by ascorbic acid are first-order in eac...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi060164d
更新日期:2006-05-09 00:00:00
abstract::By use of a mutational assay employing an octadecamer with a mismatch in the center, it is shown that the introduction of phosphorothioate groups near the 5'-end can protect the mismatch against degradation by the 5'-3'-exonuclease activity of Escherichia coli DNA polymerase I. An optimal level of protection is achiev...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00399a032
更新日期:1987-12-15 00:00:00
abstract::The Vmax/Km (microM -1 min -1.) for bovine factor X activation by bovine factor IXa alpha, in the presence of sufficient [Ca2+] to saturate the initial reaction rate, was 0.007. When factor IXa beta was substituted for factor IXa alpha in this reaction, the Vmax/Km decreased to 0.001, suggesting that factor IXa alpha ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00286a007
更新日期:1983-08-16 00:00:00
abstract::A steady-state kinetic analysis was conducted of the overall aminoacylation reaction catalyzed by isoleucyl-tRNA synthetase. The patterns of Lineweaver-Burk plots obtained indicated that tRNA adds to the enzyme only after isoleucyl adenylate formation and pyrophosphate release. These kinetic patterns were consistent w...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00580a018
更新日期:1979-06-26 00:00:00
abstract::Steroid sulfatases are responsible for the hydrolysis of 3beta-hydroxy steroid sulfates, such as cholesterol and pregnenolone sulfate, and have an important role in regulating the synthesis of estrogenic steroids, from estrone sulfate and dehydroepiandrosterone sulfate, in endocrine-dependent tumors. Although little i...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00036a025
更新日期:1995-09-12 00:00:00
abstract::Human plasma phospholipid transfer protein (PLTP) exchanges phospholipids between lipoproteins and remodels high-density lipoproteins (HDLs). We determined phospholipid transfer activity and HDL binding ability in wild-type PLTP and in 16 PLTP variants created by replacing 12 charged amino acids by site-directed mutag...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi027006g
更新日期:2003-04-22 00:00:00
abstract::Organisms rely on regulation at the molecular level, such as the allosteric regulation of hemoglobin (Hb) function by anions, to meet challenges presented by changing environmental and physiological conditions. A comparison of the effects of anions on oxygenation, oxidation, and sulfhydryl reactivity of Hb leads us to...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi971574s
更新日期:1998-01-13 00:00:00
abstract::A series of antisense oligonucleotides (ASOs) were synthesized and tested to define the best target sites within an RNA transcript of collagen for effective inhibition of expression. The test system consisted of mouse NIH 3T3 fibroblasts that were stably transfected with a human minigene for procollagen I so that the ...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00202a024
更新日期:1994-09-13 00:00:00
abstract::The aromatic residues of fd coat protein in sodium dodecyl sulfate micelles are characterized by 1H and 13C NMR. Resonances from both types of nuclei show structure-induced chemical shift dispersion and line widths indicative of a folded native structure for the protein. The two tyrosines were found to have pKas of 12...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00505a010
更新日期:1981-01-20 00:00:00
abstract::The lateral and rotational dynamics of phosphoinositides and their interactions with proteins were characterized using pyrene-labeled lipid analogues. In these systems, the collision frequency of pyrene-labeled lipids was studied by monitoring the monomeric pyrene fluorescence yield as a function of their mole fractio...
journal_title:Biochemistry
pub_type: 杂志文章
doi:10.1021/bi00028a022
更新日期:1995-07-18 00:00:00