Occurrence and Characterization of a Phosphoenolpyruvate: Glucose Phosphotransferase System in a Marine Bacterium, Serratia marinorubra
AUTOR(ES)
Hodson, Robert E.
RESUMO
The mechanism of d-glucose transport in the marine bacterium Serratia marinorubra was investigated. Uptake is mediated by a single, constitutive phosphoenolpyruvate:sugar phosphotransferase system (PTS), resulting in phosphorylation of d-glucose to d-glucose phosphate during transport. The system is saturable (Km = 6.4 × 10−6 M) and highly temperature dependent, with a Q10 of 3.5 between 5 and 15°C. The system is highly specific for d-glucose; structurally related sugars and sugar alcohols did not significantly compete with d-glucose for transport. The PTS requires Mg2+ (Km = 2.5 × 10−4 M), but its activity is otherwise unaffected by salinity changes over the range tested (0 to 35 ‰). S. marinorubra differs from other gram-negative organisms (Escherichia coli and Salmonella typhimurium) in that its glycerol (non-PTS substrate) permease is not regulated by the presence of glucose (PTS substrate).
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=291250Documentos Relacionados
- Intracellular phosphorylation of glucose analogs via the phosphoenolpyruvate: mannose-phosphotransferase system in Streptococcus lactis.
- Fractionation and characterization of the phosphoenolpyruvate: fructose 1-phosphotransferase system from Pseudomonas aeruginosa.
- Concentration-dependent repression of the soluble and membrane components of the Streptococcus mutans phosphoenolpyruvate: sugar phosphotransferase system by glucose.
- Phosphorylation of streptozotocin during uptake via the phosphoenolpyruvate: sugar phosphotransferase system in Escherichia coli.
- Genetic and Biochemical Characterization of the Phosphoenolpyruvate:Glucose/Mannose Phosphotransferase System of Streptococcus thermophilus
