Influence of ester and ether linkage in phospholipids on the environment and dynamics of the membrane interface: a wavelength-selective fluorescence approach.
We have monitored the environment and dynamics of the membrane interface formed by the ester-linked phospholipid 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and the ether-linked phospholipid 1,2-dihexadecyl-sn-glycero-3-phosphocholine (DHPC) utilizing the wavelength-selective fluorescence approach and using the fluorescent membrane probe 2-(9-anthroyloxy)stearic acid (2-AS). This interfacially localized probe offers a number of advantages over those which lack a fixed location in the membrane. When incorporated in membranes formed by DPPC and DHPC, 2-AS exhibits red edge excitation shift (REES) of 14 and 8 nm, respectively. This implies that the rate of solvent reorientation, as sensed by the interfacial anthroyloxy probe, in ester-linked DPPC membranes is slow compared to the rate of solvent reorientation in ether-linked DHPC membranes. In addition, the fluorescence polarization values of 2-AS are found to be higher in DHPC membranes than in DPPC membranes. This is further supported by wavelength-dependent changes in fluorescence polarization and lifetime. Taken together, these results are useful in understanding the role of interfacial chemistry on membrane physical properties.
Mukherjee
Soumi
S
Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500007, India.
Chattopadhyay
Amitabha
A
D004952:Esters / Q000737:chemistry*; D004987:Ethers / Q000737:chemistry*; D005454:Fluorescence Polarization; D010743:Phospholipids / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000379:methods*
D004952:Esters; D004987:Ethers; D010743:Phospholipids