No abstract

Acetate is a characteristic by-product of Escherichia coli K-12 growing in batch cultures with glucose, both under aerobic as well as anaerobic conditions. While the reason underlying aerobic acetate production is still under discussion, during anaerobic growth acetate production is important for ATP generation by substrate level phosphorylation. Under both conditions, acetate is produced by a pathway consisting of the enzyme phosphate acetyltransferase (Pta) producing acetyl-phosphate from acetyl-coenzyme A, and of the enzyme acetate kinase (AckA) producing acetate from acetyl-phosphate, a reaction that is coupled to the production of ATP. Mutants in the AckA-Pta pathway differ from each other in the potential to produce and accumulate acetyl-phosphate. In the publication at hand, we investigated different mutants in the acetate pathway, both under aerobic as well as anaerobic conditions. While under aerobic conditions only small changes in growth rate were observed, all acetate mutants showed severe reduction in growth rate and changes in the by-product pattern during anaerobic growth. The AckA − mutant showed the most severe growth defect. The glucose uptake rate and the ATP concentration were strongly reduced in this strain. This mutant exhibited also changes in gene expression. In this strain, the atoDAEB operon was significantly upregulated under anaerobic conditions hinting to the production of acetoacetate. During anaerobic growth, protein acetylation increased significantly in the ackA mutant. Acetylation of several enzymes of glycolysis and central metabolism, of aspartate carbamoyl transferase, methionine synthase, catalase and of proteins involved in translation was increased. Supplementation of methionine and uracil eliminated the additional growth defect of the ackA mutant. The data show that anaerobic, fermentative growth of mutants in the AckA-Pta pathway is reduced but still possible. Growth reduction can be explained by the lack of an important ATP generating pathway of mixed acid fermentation. An ackA deletion mutant is more severely impaired than pta or ackA-pta deletion mutants. This is most probably due to the production of acetyl-P in the ackA mutant, leading to increased protein acetylation.

The article contains sections titled: 1. History 1.1. The Spark Ignition (Otto) Engine and Its Fuel 1.2. The Diesel Engine and Its Fuel 2. Engine Technology 2.1. Otto Engines 2.2. Diesel Engines 3. Fuel Composition and Engine Efficiency 3.1. Quality Aspects of Gasoline 3.1.1. Octane Quality 3.1.2. Volatility 3.1.3. Fuel Composition to Reduce Toxicity and Exhaust Emissions 3.1.4. Stability, Cleanliness, etc 3.1.5. Performance Additives 3.2. Quality Aspects of Diesel Fuels 3.2.1. Ignition Quality 3.2.2. Density 3.2.3. Sulfur Content 3.2.4. Cold Flow Properties 3.2.5. Lubricity 3.2.6. Viscosity 3.2.7. Volatility 3.2.8. Diesel Fuel Stability, Cleanliness, etc 3.2.9. Diesel Fuel Effects on Exhaust Emissions 3.2.10. Performance Additives 4. Fuel Components 4.1. Gasoline Components 4.1.1. Straight‐Run Gasoline 4.1.2. Thermally Cracked Gasoline 4.1.3. Catalytically Cracked Gasoline 4.1.4. Catalytic Reformate (Platformate) 4.1.5. Isomerate 4.1.6. Alkylate 4.1.7. Polymer Gasoline 4.1.8. Oxygenates 4.2. Diesel Fuel Components 4.2.1. Straight‐Run Middle Distillate 4.2.2. Thermally Cracked Gas Oil 4.2.3. Catalytically Cracked Gas Oil 4.2.4. Hydrocracked Gas Oil 4.2.5. Kerosene 4.2.6. Synthetic Diesel Fuel 5. Fuel Additives 5.1. Gasoline Additives 5.1.1. Corrosion Inhibitors 5.1.2. Detergents 5.1.3. Antioxidants 5.1.4. Metal Deactivators 5.1.5. Anti‐Icing Additives 5.1.6. Additives for Combating Combustion Chamber Deposits 5.1.7. Valve Seat Recession Protection Additives 5.1.8. Antiknock Agents 5.1.9. Dehazers and Antistatic Additives 5.2. Additives for Diesel Fuel 5.2.1. Ignition Improvers (Cetane Improvers) 5.2.2. Detergent Additives 5.2.3. Cold Flow Additives 5.2.4. Lubricity Additives 5.2.5. Antifoam Additives 5.2.6. Additives for Increasing Storage Stability ‐ Antioxidants 5.2.7. Dehazers 5.2.8. Biocides 5.2.9. Antistatic Additives 5.2.10. Reodorants 6. Fuel Standardization and Testing 7. Storage and Transportation 8. Alternative Fuels

No abstract

Spirosoma linguale Migula 1894 is the type species of the genus. S. linguale is a free-living and non-pathogenic organism, known for its peculiar ringlike and horseshoe-shaped cell morphology. Here we describe the features of this organism, together with the complete genome sequence and annotation. This is only the third completed genome sequence of a member of the family Cytophagaceae. The 8,491,258 bp long genome with its eight plasmids, 7,069 protein-coding and 60 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.