MONO-VALENT CATION DEPENDENT PHASE-BEHAVIOR OF DIPALMITOYLPHOSPHATIDYLGLYCEROL
MONO-VALENT CATION DEPENDENT PHASE-BEHAVIOR OF DIPALMITOYLPHOSPHATIDYLGLYCEROL
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DOI：
10.1016/0009-3084(89)90028-5
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发表时间：
1989-04-01
影响因子：
3.4
通讯作者：
KINNUNEN, PKJ
中科院分区：
文献类型：
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作者：
EKLUND, KK;SALONEN, IS;KINNUNEN, PKJ
使用差示扫描量热法研究了二棕榈酰磷脂酰甘油 (DPPG) 与 [NaCl] 的函数关系，并比较了单价阳离子、Na+、K+、Li+ 和 Cs+ 在 300 mM 阳离子浓度下的影响。发现主相变、预相变、亚相变温度和焓取决于 NaCl 的浓度和单价阳离子种类。与主相变相比，预相变和亚相变都更敏感，并且对不同的阳离子也具有更大的特异性。在不存在盐的情况下，加热和冷却时主转变温度(Tm)的显着滞后(ΔTm)是明显的。 [NaCl]增加后，观察到ΔTm降低。当 [NaCl] 从 50 mM 增加到 1 M 时，亚相变和预相变温度以及焓增加。在高 NaCl 浓度存在下，亚相变的出现速度要快得多。 在不存在盐或存在 300 mM LiCl 的情况下，未观察到预转变。在 300 mM NaCl、KCl 和 CsCl 存在下，DPPG 的预转变温度分别为 34.0、34.3 和 30.4°C。分别为C。在 6°C 下孵育 5 天后的亚转变温度。 300 mM NaCl、KCl、CsCl 的 C 分别为 29.3、22.6 和 23.6°C。分别为C。最高亚转变温度为32.6℃。在 300 mM LiCl 存在下观察到 C，但与其他阳离子相比，在 Li+ 存在下出现亚转变需要相当长的孵育时间。
The phase behavior of dipalmitoylphosphatidylglycerol (DPPG) was studied as a function of [NaCl] using differential scanning calorimetry and the effects of monovalent cations, Na+, K+, Li+ and Cs+ were compared at 300 mM cation concentration. Main phase transition, pretransition, and subtransition temperatures and enthalpies were found to depend on the concentration of NaCl and the monovalent cation species. Compared to the main phase transition both pretransition and subtransition were more sensitive and also exerted greater specificity with respect to the different cations. Considerable hysteresis (.DELTA.Tm) in the main transition temperature (Tm) upon heating and cooling was evident in the absence of salt. Upon increasing [NaCl], a decrease in .DELTA.Tm was observed. Subtransition and pretransition temperatures and enthalpies increased upon increasing [NaCl] from 50 mM to 1 M. The appearance of subtransition was considerably faster in the presence of high NaCl concentrations. No pretransition was observed in the absence of salt or in the presence of 300 mM LiCl. Pretransition temperatures of DPPG in the presence of 300 mM NaCl, KCl, and CsCl were 34.0, 34.3 and 30.4.degree. C, respectively. The subtransition temperatures after 5 days of incubation at 6.degree. C with 300 mM NaCl, KCl, CsCl were 29.3, 22.6 and 23.6.degree. C, respectively. The highest subtransition temperature of 32.6.degree. C was observed in the presence of 300 mM LiCl but compared to other cations the appearance of subtransition in the presence of Li+ required considerably longer incubation times.