Assays

Enzymes involved in butanediol formation from pyruvate in L. Lactis and E. faecalis were characterized with respect to their Km's for their substrates and their Vmaxes

L. lactis, E. faecalis and S. pyogenes are referred to as LAB because of the fact that in the presence of glucose lactate is produced as the main fermentation product . This metabolic pathway is relatively inefficient, since only 2 ATP are generated from one glucose molecule. All three LAB possess the genetic make up for mixed acid fermentation, a more effective way of fermentation generating 3 ATP per molecule of glucose. All three genomes reveal (at least) two genes encoding a lactate dehydrogenase ...

L. lactis, S. pyogenes and E. faecalis were grown in C-limited chemostat cultures at various pH's and dilution rates. General flux distribution, yields and other physiological factors were studied.

In this experiment we glucose-pulsed an E. faecalis cultures re-suspended in 100 mM MES buffer at pH 6.5. Samples were taken in time to study intra- and extracellular metabolites. These data are used to construct a kinetic model of the catqabolism of E. faecalis

In this experiment we glucose-pulsed an L. lactiss cultures re-suspended in 100 mM MES buffer at pH 6.5. Samples were taken in time to study intra- and extracellular metabolites. These data are used to construct a kinetic model of the catabolism of E. L. lactis

Determination of essential amino acids for Streptococcus pyogenes

Km values of pyruvate kinase of different organisms without/with allosteric effector molecules collected from literature.

S. pyogenes wildetype, an arcA- and a glnA-deletion mutants were grown in CDM-LAB cultures at pH 6.5 and 7.5 and at a growth rate of 0.05

In order to construct an in vivo-like buffer for S. pyogenes, the intracellular concentrations of Fe, K, Mg, Mn Na, P and S elements were determined via ICP-AES (inductively coupled plasma atomic emissionspectroscopy) method at the Institute of Land Use, University of Rostock. The samples for the analysis were obtained from a steady state culture grown on CDM-LAB with glucose.

S. pyogenes M49 (591), E. faecalis V583, and L. lacis NZ9000 and their isogenic ldh deletion mutants were grown glucose free CDM-LAB medium in BIOLOG phenotype microarray plates PM01 and PM02. With this assay the abilitiy of the strains to grow on 190 different carbon sources was determined in 96 well format.

L. lactis was grown in LAB medium or rich THY medium, strongly concentrated and glucose-pulsed in a MES buffer. Intracellular metabolite concentration is followed in time.

Measurements on Km, Vmax and allosteric activation or inhibition of the heterologously expressed (E. coli) and purifiied main L-lactate dehydrogenase

Measurements on Km, Vmax and allosteric activation or inhibition of the main L-lactate dehydrogenase

Global sensitivity analysis of a kinetic model to determine the sensitivities for each parameter, over a wide parameter range. We used the elementary effects method.

Lumped kinetic model of L. lactis glycolysis, formulated with ordinary differential equations. Simulations are in line with experimental data

S. pyogenes was grown in rich medium, strongly concentrated and glucose-pulsed in a MES buffer. Intracellular metabolite concentration is followed in time.

Despite high similarity in sequence and catalytic properties, the L-lactate dehydrogenases (LDH) in lactic acid bacteria (LAB) display differences in their regulation which may arise from their adaptation to different habitats. We combined experimental and computational approaches to investigate the effects of fructose-1,6-bisphosphate (FBP), phosphate (Pi) and ionic strength (NaCl concentration) on 6 LDHs from 4 LABs studied at pH 6 and pH 7. We find: (1) The extent of activation by FBP (Kact) ...

Pyruvate formate-lyase (PFL) is an important enzyme in the metabolic pathway of lactic acid bacteria (LAB) and is held responsible for the regulation of the shift between homolactic acid to mixed acid fermentation. PFL catalysis the reversible reaction of acetyl-CoA and formate into pyruvate and CoA. A glycyl radical, who is regenerated within the reaction, is involved; therefore, PFL works only under strictly anaerobic conditions. For its activation, the C-terminal domain has to bind to the ...

Metabolic network of S. pyogenes including primary metabolism, polysaccharide metabolism, purine and pyrimidine biosoynthesis, teichoic acid biosynthesis, fatty acid and phospholipid bioynthesis, amino acid metabolism, vitamins and cofactors

Metabolic network of Enterococcus faecalis including primary metabolism, polysaccharide metabolism, purine and pyrimidine biosoynthesis, teichoic acid biosynthesis, fatty acid and phospholipid bioynthesis, amino acid metabolism, vitamins and cofactors