A Pseudomonas putida cardiolipin synthesis mutant exhibits increased sensitivity to drugs related to transport functionality

被引:76
作者
Bernal, Patricia
Munoz-Rojas, Jesus
Hurtado, Ana
Ramos, Juan L.
Segura, Ana
机构
[1] CSIC, Estac Expt Zaidin, Dept Environm Protect, E-18008 Granada, Spain
[2] CICM, ICUAP, BUAP, Puebla, Mexico
关键词
D O I
10.1111/j.1462-2920.2006.01236.x
中图分类号
Q93 [微生物学];
学科分类号
071005 ; 100705 ;
摘要
Biological membranes have evolved different mechanisms to modify their composition in response to chemical stimuli in a process called 'homeoviscous adaptation'. Among these mechanisms, modifications in the ratio of saturated/unsaturated fatty acids and in cis/trans fatty acid isomers, cyclopropanation and changes in the phospholipids head group composition have been observed. To further understand the role of phospholipid head groups in solvent stress adaptation, we knocked out the cls (cardiolipin synthase) gene in Pseudomonas putida DOT-T1E. As expected, cis mutant membranes contained less cardiolipin than those of the wild-type strain. Although no significant growth rate defect was observed in the cis mutant compared with the wild-type strain, mutant cells were significantly smaller than the wild-type cells. The cls mutant was more sensitive to toluene shocks and to several antibiotics than the parental strain, suggesting either that the RND efflux pumps involved in the extrusion of these drugs were not working efficiently or that membrane permeability was altered in the mutant. Membranes of the cis mutant strain seemed to be more rigid than those of the parental strain, as observed by measurements of fluorescence polarization using the DPH probe, which intercalates into the membranes. Ethidium bromide is pumped out in Pseudomonas putida by at least one RND efflux pump involved in antibiotic and solvent resistance, and the higher rate of accumulation of ethidium bromide inside mutant cells indicated that functioning of the efflux pumps was compromised as a consequence of the alteration in phospholipid head group composition.
引用
收藏
页码:1135 / 1145
页数:11
相关论文
共 57 条
[1]   REGULATOR AND ENZYME SPECIFICITIES OF THE TOL PLASMID-ENCODED UPPER PATHWAY FOR DEGRADATION OF AROMATIC-HYDROCARBONS AND EXPANSION OF THE SUBSTRATE RANGE OF THE PATHWAY [J].
ABRIL, MA ;
MICHAN, C ;
TIMMIS, KN ;
RAMOS, JL .
JOURNAL OF BACTERIOLOGY, 1989, 171 (12) :6782-6790
[3]  
[Anonymous], PSEUDOMONAS
[4]  
[Anonymous], 1991, ANTIBIOTICS LAB MED
[5]   Lipid-layer crystallization and preliminary three-dimensional structural analysis of AcrA, the periplasmic component of a bacterial multidrug efflux pump [J].
Avila-Sakar, AJ ;
Misaghi, S ;
Wilson-Kubalek, EM ;
Downing, KH ;
Zgurskaya, H ;
Nikaido, H ;
Nogales, E .
JOURNAL OF STRUCTURAL BIOLOGY, 2001, 136 (01) :81-88
[6]  
BLIGH EG, 1959, CAN J BIOCHEM PHYS, V37, P911
[7]   A polytopic membrane protein displays a reversible topology dependent on membrane lipid composition [J].
Bogdanov, M ;
Heacock, PN ;
Dowhan, W .
EMBO JOURNAL, 2002, 21 (09) :2107-2116
[8]  
CASTUMA CE, 1993, J BIOL CHEM, V268, P24665
[9]   Membrane cyclopropane fatty acid content is a major factor in acid resistance of Escherichia coli [J].
Chang, YY ;
Cronan, JE .
MOLECULAR MICROBIOLOGY, 1999, 33 (02) :249-259
[10]   Global and cognate regulators control the expression of the organic solvent efflux pumps TtgABC and TtgDEF of Pseudomonas putida [J].
Duque, E ;
Segura, A ;
Mosqueda, G ;
Ramos, JL .
MOLECULAR MICROBIOLOGY, 2001, 39 (04) :1100-1106