Optimization of Phosphatidylserine-Modified Titanium Surfaces for Enhanced Osteoblast Response

2006 ◽  
Author(s):  
Neera Satsangi ◽  
Arpan Satsangi ◽  
Joo L. Ong ◽  
Rajiv V. Satsangi
Keyword(s):  
Alkaline Phosphatase ◽  
Protein Production ◽  
Specific Activity ◽  
Acyl Chain ◽  
Fatty Acyl ◽  
Separate Experiment ◽  
Calcium Deposition ◽  
Fatty Acyl Chain ◽  
Acyl Chain Length

This report is part of a continued effort to evaluate the in vitro osteoblast responses on different phospholipid coatings on Titanium (Ti) implant materials. It has been established that, among analogous phopholipids, the Ti surfaces coated with calcium phosphate (CaP) complex of phosphatidylserine induce the best calcium deposition and osteoblast growth and metabolism. This communication describes an effort to optimize the chemical structure of phosphatidylserine at its position−1 and −2, as Ti surface coating relative to enhancement in osteoblast differentiation and growth in culture. Four synthetic phosphatidylserine analogs with varying fatty acyl chain length and unsaturation were converted to CaP complex, coated on Ti discs, and the osteoblast progenitor cells were cultured on them for up to 14 days to study their differentiation, growth and biochemistry as marked by the expression of alkaline phosphatase specific activity and protein production. In a separate experiment, the topography of the glass surface (glass Petri-dishes) coated the analogous phosphatidylserines, after immersion in simulated body fluid, was examined by scanning electron microscopy (SEM). The presence of calcium and phosphate ions in this deposit was also confirmed. The inclusion of unsaturation in fatty acyl chain in phosphatidylserine enhanced the Total protein production (TPP) as well as the alkaline phosphatase (ALP) specific activity.

Effect of Acylglycerol Composition and Fatty Acyl Chain Length on Lipid Digestion in pH-Stat Digestion Model and SimulatedIn VitroDigestion Model

2015 ◽  
Vol 81 (2) ◽  
pp. C317-C323
Author(s):  
Jin F. Qi ◽  
Cai H. Jia ◽  
Jung A. Shin ◽  
Jeong M. Woo ◽  
Xiang Y. Wang ◽  
...  
Keyword(s):  
Chain Length ◽  
Acyl Chain ◽  
Fatty Acyl ◽  
Fatty Acyl Chain ◽  
Lipid Digestion ◽  
Acyl Chain Length ◽  
Ph Stat

scholarly journals Ectopic expression of ceramide synthase 2 in neurons suppresses neurodegeneration induced by ceramide synthase 1 deficiency

2016 ◽  
Vol 113 (21) ◽  
pp. 5928-5933 ◽  
Author(s):  
Stefka D. Spassieva ◽  
Xiaojie Ji ◽  
Ye Liu ◽  
Kenneth Gable ◽  
Jacek Bielawski ◽  
...  
Keyword(s):  
Acyl Chain ◽  
Strong Association ◽  
Ectopic Expression ◽  
Fatty Acyl ◽  
Chemical Diversity ◽  
Fatty Acyl Chain ◽  
Length Variation ◽  
Ceramide Synthase ◽  
Hydrophobic Moiety

Sphingolipids exhibit extreme functional and chemical diversity that is in part determined by their hydrophobic moiety, ceramide. In mammals, the fatty acyl chain length variation of ceramides is determined by six (dihydro)ceramide synthase (CerS) isoforms. Previously, we and others showed that mutations in the major neuron-specific CerS1, which synthesizes 18-carbon fatty acyl (C18) ceramide, cause elevation of long-chain base (LCB) substrates and decrease in C18 ceramide and derivatives in the brain, leading to neurodegeneration in mice and myoclonus epilepsy with dementia in humans. Whether LCB elevation or C18 ceramide reduction leads to neurodegeneration is unclear. Here, we ectopically expressed CerS2, a nonneuronal CerS producing C22–C24 ceramides, in neurons of Cers1-deficient mice. Surprisingly, the Cers1 mutant pathology was almost completely suppressed. Because CerS2 cannot replenish C18 ceramide, the rescue is likely a result of LCB reduction. Consistent with this hypothesis, we found that only LCBs, the substrates common for all of the CerS isoforms, but not ceramides and complex sphingolipids, were restored to the wild-type levels in the Cers2-rescued Cers1 mutant mouse brains. Furthermore, LCBs induced neurite fragmentation in cultured neurons at concentrations corresponding to the elevated levels in the CerS1-deficient brain. The strong association of LCB levels with neuronal survival both in vivo and in vitro suggests high-level accumulation of LCBs is a possible underlying cause of the CerS1 deficiency-induced neuronal death.

Lipid profiling of human diabetic myocardium reveals differences in triglyceride fatty acyl chain length and degree of saturation

2020 ◽  
Vol 320 ◽  
pp. 106-111
Author(s):  
Elias Björnson ◽  
Ylva Östlund ◽  
Marcus Ståhlman ◽  
Martin Adiels ◽  
Elmir Omerovic ◽  
...  
Keyword(s):  
Chain Length ◽  
Acyl Chain ◽  
Fatty Acyl ◽  
Degree Of Saturation ◽  
Fatty Acyl Chain ◽  
Lipid Profiling ◽  
Acyl Chain Length ◽  
Diabetic Myocardium

scholarly journals Fatty Acyl Benzamido Antibacterials Based on Inhibition of DnaK-catalyzed Protein Folding

2006 ◽  
Vol 282 (7) ◽  
pp. 4437-4446 ◽  
Author(s):  
Markus Liebscher ◽  
Günther Jahreis ◽  
Christian Lücke ◽  
Susanne Grabley ◽  
Satish Raina ◽  
...  
Keyword(s):  
Protein Folding ◽  
Minimal Inhibitory Concentration ◽  
Inhibitory Concentration ◽  
Acyl Chain ◽  
Fatty Acyl ◽  
Secondary Amide ◽  
Fatty Acyl Chain ◽  
Isomerase Activity

We have reported that the hsp70 chaperone DnaK from Escherichia coli might assist protein folding by catalyzing the cis/trans isomerization of secondary amide peptide bonds in unfolded or partially folded proteins. In this study a series of fatty acylated benzamido inhibitors of the cis/trans isomerase activity of DnaK was developed and tested for antibacterial effects in E. coli MC4100 cells. Nα-[Tetradecanoyl-(4-aminomethylbenzoyl)]-l-asparagine is the most effective antibacterial with a minimal inhibitory concentration of 100 ± 20 μg/ml. The compounds were shown to compete with fluorophore-labeled σ32-derived peptide for the peptide binding site of DnaK and to increase the fraction of aggregated proteins in heat-shocked bacteria. Despite its inability to serve as a folding helper in vivo a DnaK-inhibitor complex was still able to sequester an unfolded protein in vitro. Structure activity relationships revealed a distinct dependence of DnaK-assisted refolding of luciferase on the fatty acyl chain length, whereas the minimal inhibitory concentration was most sensitive to the structural nature of the benzamido core. We conclude that the isomerase activity of DnaK is a major survival factor in the heat shock response of bacteria and that small molecule inhibitors can lead to functional inactivation of DnaK and thus will display antibacterial activity.

scholarly journals Improved reconstitution of yeast vacuole fusion with physiological SNARE concentrations reveals an asymmetric Rab(GTP) requirement

2016 ◽  
Vol 27 (16) ◽  
pp. 2590-2597 ◽  
Author(s):  
Michael Zick ◽  
William Wickner
Keyword(s):  
Acyl Chain ◽  
Fatty Acyl ◽  
Fatty Acyl Chain ◽  
Rab Gtpase ◽  
Lower Phase ◽  
Yeast Vacuole ◽  
Vacuole Fusion ◽  
In Vitro Reconstitution

In vitro reconstitution of homotypic yeast vacuole fusion from purified components enables detailed study of membrane fusion mechanisms. Current reconstitutions have yet to faithfully replicate the fusion process in at least three respects: 1) The density of SNARE proteins required for fusion in vitro is substantially higher than on the organelle. 2) Substantial lysis accompanies reconstituted fusion. 3) The Rab GTPase Ypt7 is essential in vivo but often dispensable in vitro. Here we report that changes in fatty acyl chain composition dramatically lower the density of SNAREs that are required for fusion. By providing more physiological lipids with a lower phase transition temperature, we achieved efficient fusion with SNARE concentrations as low as on the native organelle. Although fused proteoliposomes became unstable at elevated SNARE concentrations, releasing their content after fusion had occurred, reconstituted proteoliposomes with substantially reduced SNARE concentrations fused without concomitant lysis. The Rab GTPase Ypt7 is essential on both membranes for proteoliposome fusion to occur at these SNARE concentrations. Strikingly, it was only critical for Ypt7 to be GTP loaded on membranes bearing the R-SNARE Nyv1, whereas the bound nucleotide of Ypt7 was irrelevant on membranes bearing the Q-SNAREs Vam3 and Vti1.

scholarly journals Dependence of fatty acyl chain length on the property of phase separation of GM3/DPPC multilamellar vesicles

2001 ◽  
Vol 41 (supplement) ◽  
pp. S128
Author(s):  
S. Matsuoka ◽  
M. Akiyama ◽  
H. Yamada ◽  
K. Tsuchihashi ◽  
S. Gasa
Keyword(s):  
Phase Separation ◽  
Chain Length ◽  
Acyl Chain ◽  
Fatty Acyl ◽  
Fatty Acyl Chain ◽  
Multilamellar Vesicles ◽  
Acyl Chain Length

scholarly journals Mapping the catalytic pocket of phospholipases A2 and C using a novel set of phosphatidylcholines

2000 ◽  
Vol 346 (3) ◽  
pp. 679-690 ◽  
Author(s):  
Julio J. CARAMELO ◽  
Jorge FLORÍN-CHRISTENSEN ◽  
Mónica FLORÍN-CHRISTENSEN ◽  
José M. DELFINO
Keyword(s):  
Acyl Chain ◽  
Binding Pocket ◽  
Narrow Channel ◽  
Fatty Acyl ◽  
Fatty Acyl Chain ◽  
Crystallographic Structure ◽  
Naja Naja ◽  
Phospholipases A2 ◽  
Acyl Chain Length ◽  
Hydrolytic Activities

A set of radioiodinatable phosphatidylcholines (PCs) derivatized with the Bolton-Hunter reagent (BHPCs) was synthesized to probe the substrate recognition and activity of phospholipases. A common feature of this series is the presence of a bulky 4-hydroxyphenyl group at the end of the fatty acyl chain attached to position sn-2. The distance between the end group and the glycerol backbone was varied by changing the length of the intervening fatty acyl chain (3-25 atoms). Except for the shortest, this chain includes at least one amide linkage. The usefulness of this series of substrates as a molecular ruler was tested by measuring the hydrolytic activities of Naja naja naja phospholipase A2 (PLA2) and Bacillus cereus phospholipase C (PLC) in Triton X-100 micelles. The activity of PLA2 proved to be highly dependent on the length of the fatty acyl chain linker, the shorter compounds (3-10 atoms) being very poor substrates. In contrast, the PLC activity profile exhibited much less discrimination. In both cases, PCs with 16-21 atom chains at position sn-2 yielded optimal activity. We interpret these findings in terms of fatty acyl chain length-related steric hindrance caused by the terminal aromatic group, affecting the activity of PLA2 and, to a smaller extent, that of PLC. This notion agrees with the more extended recognition of aliphatic chains inside the narrow channel leading to the catalytic site in the former case. Molecular models of these substrates bound to PLA2 were built on the basis of the crystallographic structure of Naja naja atra PLA2 complexed with a phospholipid analogue. Docking of these substrates necessarily requires the intrusion of the bulky 4-hydroxyphenyl group inside the binding pocket and also the failure of the amide group to form hydrogen bonds inside the hydrophobic substrate channel.

Ketoacyl synthase domain is a major determinant for fatty acyl chain length in Saccharomyces cerevisiae

2013 ◽  
Vol 195 (12) ◽  
pp. 843-852 ◽  
Author(s):  
Juthaporn Sangwallek ◽  
Yoshinobu Kaneko ◽  
Minetaka Sugiyama ◽  
Hisayo Ono ◽  
Takeshi Bamba ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Chain Length ◽  
Acyl Chain ◽  
Fatty Acyl ◽  
Major Determinant ◽  
Fatty Acyl Chain ◽  
Acyl Chain Length ◽  
Ketoacyl Synthase
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