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E L Martin

Publications and source records attributed to E L Martin.

22 records · Page 2Linked to original sources
PubMed1975

Kinetics of Naplus-dependent amino acid transport using cells and membrane vesicles of a marine pseudomonad.

Sodium ion is required for transport of L-alanine and alpha-aminoisobutyric acid (AIB) into cells and membrane vesicles of a marine pseudomonad. Initial rate data obtained at various Naplus and amino acid concentrations were tested for fit by least squares analysis to sequential and Ping-Pong equations. The sequential case is preferred statistically at the 99% confidence limit. Cotransport of AIB and Naplus in cells could not be detected, perhaps explained by efflux of Naplus shown to occur from these cells. The kinetic analysis is consistent with formation of a ternary complex involving Naplus and the amino acid.

Alanine↗
PubMed1971

Isolation and chemical composition of the cytoplasmic membrane of a gram-negative bacterium.

With procedures developed previously in this laboratory, the various layers of the cell wall of a gram-negative bacterium, a marine pseudomonad (ATCC 19855), were removed completely giving rise to true protoplasts. Membranes were isolated from the protoplasts formed. After treatment with ribonuclease, deoxyribonuclease, and washing, the membranes isolated were shown by electron microscopy and chemical analysis to be essentially free from both wall material and cytoplasmic constituents. The membranes gave rise to a single compact band in a sucrose density gradient. All of the lipid and protein were found to be associated in the membrane band. Analysis showed the membranes to contain 30.5% lipid (78% of which was phospholipid), 62.8% protein, and 2% carbohydrate. The predominant phospholipid present was phosphatidylethanolamine with a lesser amount of diphosphatidylglycerol and traces of unidentified compounds.

Bacterial Proteins↗