Phosphatidyl Serine

Baer, Erich; Maurukas, Jonas

doi:10.1016/s0021-9258(18)71090-9

Cited by 92 publications

(5 citation statements)

References 22 publications

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“…By comparison with the results for other anhydrous lipids (Finean, 1956;Ladbrooke & Chapman, 1969;, it can be concluded that the lipid chains melt at this temperature, rather than the lipid as a whole as was previously assumed (MacDonald et al, 1976). The capillary melting point of our DMPS preparations was 163-165 °C (159-161 °C for DPPS), in agreement with the original result of Baer & Maurukas (1955). The high-temperature phase can thus be identified as L" and, by analogy with other lipids, the low-temperature phase is identified as being one of the L^types (Tardieu et al, 1973;Janiak et al, 1976).…”

Section: Discussionsupporting

confidence: 90%

Titration of the phase transition of phosphatidylserine bilayer membranes. Effects of pH, surface electrostatics, ion binding, and head-group hydration

Cevc¹,

Watts²,

Marsh³

1981

Biochemistry

243

161

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The dependence of the gel-to-fluid phase transition temperature of dimyristoyl- and dipalmitoylphosphatidylserine bilayers on pH, NaCl concentration, and degree of hydration has been studied with differential scanning calorimetry and with spin-labels. On protonation of the carboxyl group (pK2app = 5.5), the transition temperature increases from 36 to 44 degrees C in the fully hydrated state of dimyristoylphosphatidylserine (from 54 to 62 degrees C for dipalmitoylphosphatidylserine), at ionic strength J = 0.1. In addition, at least two less hydrated states, differing progressively by 1 H2O/PS, are observed at low pH with transition temperatures of 48 and 52 degrees C for dimyristoyl- and 65 and 68.5 degrees C for dipalmitoylphosphatidylserine. On deprotonation of the amino group (pK3app = 11.55) the transition temperature decreases to approximately 15 degrees C for dimyristoyl- and 32 degrees C for dipalmitoylphosphatidylserine, and a pretransition is observed at approximately 6 degrees C (dimyristoylphosphatidylserine) and 21.5 degrees C (dipalmitoylphosphatidylserine), at J = 0.1. No titration of the transition is observed for the fully hydrated phosphate group down to pH less than or equal to 0.5, but it affinity for water binding decreases steeply at pH greater than or equal to 2.6. Increasing the NaCl concentration from 0.1 to 2.0 M increases the transition temperature of dimyristoyphosphatidylserine by approximately 8 degrees C at pH 7, by approximately 5 degrees at pH 13, and by approximately 0 degrees C at pH 1. These increases are attributed to the screening of the electrostatic titration-induced shifts in transition temperature. On a further increase of the NaCl concentration to 5.5 M, the transition temperature increases by an additional 9 degree C at pH 7, 13 degree C at pH 13, approximately 7 degree C in the fully hydrated state at pH 1, and approximately 4 and approximately 0 degree C in the two less hydrated states. These shifts are attributed to displacement of water of hydration by ion binding. From the salt dependence it is deduced that the transition temperature shift at the carboxyl titration can be accounted for completely by the surface charge and change in hydration of approximately 1 H2O/lipid, whereas that of the amino group titration arises mostly from other sources, probably hydrogen bonding. The shifts in pK (delta pK2 = 2.85, delta pK3 = 1.56) are consistent with a reduced polarity in the head-group region, corresponding to an effective dielectric constant epsilon approximately or equal to 30, together with surface potentials of psi congruent to -100 and -150 mV at the carboxyl and amino group pKs, respectively. The transition temperature of dimyristoylphosphatidylserine-water mixtures decreases by approximately 4 degree C each water/lipid molecule added, reaching a limiting value at a water content of approximately 9-10 H2O/lipid molecule.

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Section: Discussionsupporting

confidence: 90%

Titration of the phase transition of phosphatidylserine bilayer membranes. Effects of pH, surface electrostatics, ion binding, and head-group hydration

Cevc¹,

Watts²,

Marsh³

1981

Biochemistry

243

161

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“…The following compounds were prepared by the described procedures, or by minor modifications of these procedures, (a) A-Carbobenzoxy-L-serine, by the method of Moore et al (1954), was obtained in 78% yield and showed the expected elemental analyses mp 118-119°, [a]o +5.83°(c 6, acetic acid). These values conform to those reported in the literature (Moore et Baer and Maurukas, 1955;Fruton, 1942). (b) A-Carbobenzoxy-L-serine benzyl ester, by the method of Ben-Ishai and Berger (1952), was obtained in 75 % yield and showed the expected elemental analyses mp 84-85°, [«] +6.1°(c 4, chloroform).…”

Section: Materials and Methods2supporting

confidence: 90%

“…These values agreed with those reported by Baer and Maurukas (1955). °The molar rotations of the glycosylserines were not corrected for the contribution by the L-serine ([M]d = -717°i n water); the effect of pH on the rotations was not studied.…”

Section: Materials and Methods2supporting

confidence: 87%

The Synthesis of O-Serine Glycosides^*

Kum¹,

Roseman²

1966

Biochemistry

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“…The procedure previously employed for ( R )- 10 18 and ( R , S )- 10 was also used to synthesize ( S )- 10 . Synthesis of ( R )-, ( S )-, and ( R , S )- 10 began with readily available Cbz- d -, Cbz- l -, and Cbz- dl -serine (( R )-, ( S )-, and ( R , S )- 11 ), respectively . Compound 11 was converted to 12 using benzylamine and the mixed-anhydride coupling (MAC) procedure .…”

Section: Resultsmentioning

confidence: 99%

Design and Evaluation of Affinity Labels of Functionalized Amino Acid Anticonvulsants

2002

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Studies have shown that functionalized amino acids (FAA) exhibit outstanding activity in the maximal electroshock-induced seizure (MES) test in rodents. Affinity labels patterned in part after the potent antiepileptic (R)-N-benzyl-2-acetamido-3-methoxypropionamide ((R)-2) have been prepared as mechanistic probes to learn the pharmacological basis for FAA function. The chemical reactivity of the affinity labels with nucleophiles was assessed, and the labels were evaluated in in vitro radioligand assays and in the MES tests in rodents. The affinity labels did not bind to receptors known to effect seizure spread. Three affinity labels, (R,S)-N-benzyl-2-acetamido-6-isothiocyanatohexanamide ((R,S)-5), (R)-N-(4-isothiocyanatobenzyl)-2-acetamido-3-methoxypropionamide ((R)-6), and (R)-N-(3-isothiocyanatobenzyl)-2-acetamido-3-methoxypropionamide ((R)-7), possessed excellent in vivo anticonvulsant activity and exhibited maximal activity at later time periods than typically observed for FAA. The anticonvulsant activity of 6 and 7 resided primarily in the (R)-enantiomer and the activity of (R)-6 and (R)-7 in rats (po) exceeded that of phenytoin. The chemical properties, pharmacological profile, and marked stereospecificity associated with 6 and 7 anticonvulsant activity make these compounds useful pharmacological tools for the study of the mode of action of FAA.

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Phosphatidyl Serine

Cited by 92 publications

References 22 publications

Titration of the phase transition of phosphatidylserine bilayer membranes. Effects of pH, surface electrostatics, ion binding, and head-group hydration

Titration of the phase transition of phosphatidylserine bilayer membranes. Effects of pH, surface electrostatics, ion binding, and head-group hydration

The Synthesis of O-Serine Glycosides^*

Design and Evaluation of Affinity Labels of Functionalized Amino Acid Anticonvulsants

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Phosphatidyl Serine

Cited by 92 publications

References 22 publications

Titration of the phase transition of phosphatidylserine bilayer membranes. Effects of pH, surface electrostatics, ion binding, and head-group hydration

Titration of the phase transition of phosphatidylserine bilayer membranes. Effects of pH, surface electrostatics, ion binding, and head-group hydration

The Synthesis of O-Serine Glycosides*

Design and Evaluation of Affinity Labels of Functionalized Amino Acid Anticonvulsants

Contact Info

Product

Resources

About

The Synthesis of O-Serine Glycosides^*