0000000000958851
AUTHOR
Célia Roussel
Additional file 6: Table S1. of Characterization of two Lactococcus lactis zinc membrane proteins, Llmg_0524 and Llmg_0526, and role of Llmg_0524 in cell wall integrity
Strains and plasmids. (PDF 355 kb)
Additional file 2: Figure S2. of Characterization of two Lactococcus lactis zinc membrane proteins, Llmg_0524 and Llmg_0526, and role of Llmg_0524 in cell wall integrity
Deletion of llmg_0524 or llmg_0526 decreases modestly operon expression. The plasmid P0524-pTCV-lac is established in mutant ∆llmg_0524 and ∆llmg_0526. Cells were grown in M17Glu0.5 up to OD600= 0.1 for β-galactosidase determination. Results, plus standard deviation, are means of three independent experiments. They are expressed in percentage of values of wild type strain. (PDF 171 kb)
Additional file 4: Figure S4. of Characterization of two Lactococcus lactis zinc membrane proteins, Llmg_0524 and Llmg_0526, and role of Llmg_0524 in cell wall integrity
UV-visible spectra of protein fusions. 20 μM of proteins were used. Analysis was performed in 50 mM Tris–HCl buffer, pH 7.4, at room temperature with a Libra S22 spectrophotometer. (PDF 193 kb)
Additional file 1: Figure S1. of Characterization of two Lactococcus lactis zinc membrane proteins, Llmg_0524 and Llmg_0526, and role of Llmg_0524 in cell wall integrity
Amino acid sequence of Llmg_0524 and Llmg_0526. Llmg_0524 has 200 amino-acid residues, including four cysteines in the Nter region and two transmembrane domains (TMDs). Llmg_0526 has 421 amino-acid residues, including four cysteines in the Nter region and a transmembrane domain. The cysteine residues cluster in a CX2CX10CX2C motif in both proteins. Cysteine amino-acid residues are in bold red; predicted membrane helices are in bold black. (PDF 304 kb)
Additional file 6: Table S1. of Characterization of two Lactococcus lactis zinc membrane proteins, Llmg_0524 and Llmg_0526, and role of Llmg_0524 in cell wall integrity
Strains and plasmids. (PDF 355 kb)
Understanding of the physiological and genetic mechanisms involved in the reducing activity of Lactococcus lactis
Lactic acid bacteria, particularly Lactococcus lactis are used in dairy industry. These bacteria are known to have a reducing activity, indicating their ability to lower the redox potential (Eh) of a medium. L. lactis MG1363 genome encodes several proteins with a CXXC motif, potentially linked with a redox activity. To understand the role of proteins rich in cysteine located at the surface of L. lactis, two approaches were used, one bioinformatics and biochemical another. For bioinformatic approach, interest was focused on two proteins of unknown function and CX2CX10CX2C motif: Llmg_0524 and Llmg_0526. Their corresponding genes form an operon temporarily induces in early growth phase. In th…
Additional file 3: Figure S3. of Characterization of two Lactococcus lactis zinc membrane proteins, Llmg_0524 and Llmg_0526, and role of Llmg_0524 in cell wall integrity
Determination of PhoA activity of different fusion proteins. Data are the means of results, ± standard deviations, from three independent experiments. PhoA1 contains only the Nter extremity whereas PhoA2 contains the Nter extremity and the predicted transmembrane domain. (PDF 178 kb)
Additional file 5: Table S2. of Characterization of two Lactococcus lactis zinc membrane proteins, Llmg_0524 and Llmg_0526, and role of Llmg_0524 in cell wall integrity
Proteins containing the CX2CX10CX2C motif in various bacterial species. (PDF 512 kb)
Additional file 5: Table S2. of Characterization of two Lactococcus lactis zinc membrane proteins, Llmg_0524 and Llmg_0526, and role of Llmg_0524 in cell wall integrity
Proteins containing the CX2CX10CX2C motif in various bacterial species. (PDF 512 kb)
Characterization of two Lactococcus lactis zinc membrane proteins, Llmg_0524 and Llmg_0526, and role of Llmg_0524 in cell wall integrity
Background Due to its extraordinary chemical properties, the cysteine amino acid residue is often involved in protein folding, electron driving, sensing stress, and binding metals such as iron or zinc. Lactococcus lactis, a Gram-positive bacterium, houses around one hundred cysteine-rich proteins (with the CX2C motif) in the cytoplasm, but only a few in the membrane. Results In order to understand the role played by this motif we focused our work on two membrane proteins of unknown function: Llmg_0524 and Llmg_0526. Each of these proteins has two CX2C motifs separated by ten amino-acid residues (CX2CX10CX2C). Together with a short intervening gene (llmg_0525), the genes of these two protein…