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Ca 2+ -Citrate Uptake and Metabolism in Lactobacillus casei ATCC 334
- Source :
- Applied and environmental microbiology, 79(15), 4603-4612. AMER SOC MICROBIOLOGY, CONICET Digital (CONICET), Consejo Nacional de Investigaciones Científicas y Técnicas, instacron:CONICET
- Publication Year :
- 2013
- Publisher :
- American Society for Microbiology, 2013.
-
Abstract
- The putative citrate metabolic pathway in Lactobacillus casei ATCC 334 consists of the transporter CitH, a proton symporter of the citrate-divalent metal ion family of transporters CitMHS, citrate lyase, and the membrane-bound oxaloacetate decarboxylase complex OAD-ABDH. Resting cells of Lactobacillus casei ATCC 334 metabolized citrate in complex with Ca 2+ and not as free citrate or the Mg 2+ -citrate complex, thereby identifying Ca 2+ -citrate as the substrate of the transporter CitH. The pathway was induced in the presence of Ca 2+ and citrate during growth and repressed by the presence of glucose and of galactose, most likely by a carbon catabolite repression mechanism. The end products of Ca 2+ -citrate metabolism by resting cells of Lb. casei were pyruvate, acetate, and acetoin, demonstrating the activity of the membrane-bound oxaloacetate decarboxylase complex OAD-ABDH. Following pyruvate, the pathway splits into two branches. One branch is the classical citrate fermentation pathway producing acetoin by α-acetolactate synthase and α-acetolactate decarboxylase. The other branch yields acetate, for which the route is still obscure. Ca 2+ -citrate metabolism in a modified MRS medium lacking a carbohydrate did not significantly affect the growth characteristics, and generation of metabolic energy in the form of proton motive force (PMF) was not observed in resting cells. In contrast, carbohydrate/Ca 2+ -citrate cometabolism resulted in a higher biomass yield in batch culture. However, also with these cells, no generation of PMF was associated with Ca 2+ -citrate metabolism. It is concluded that citrate metabolism in Lb. casei is beneficial when it counteracts acidification by carbohydrate metabolism in later growth stages.
- Subjects :
- ATP citrate lyase
Physiology
Carboxy-Lyases
Catabolite repression
Metabolic energy
Applied Microbiology and Biotechnology
Substrate Specificity
purl.org/becyt/ford/1 [https]
chemistry.chemical_compound
Citrate synthase
Chromatography, High Pressure Liquid
0303 health sciences
Ecology
biology
Acetoin
Bioquímica y Biología Molecular
Lacticaseibacillus casei
Biochemistry
DEPENDENT PHOSPHOTRANSFERASE SYSTEM
Carbohydrate Metabolism
Colorimetry
KLEBSIELLA-PNEUMONIAE
Lactobacillus casei
CIENCIAS NATURALES Y EXACTAS
Biotechnology
CITRATE METABOLISM
Citric Acid Cycle
ENTEROCOCCUS-FAECALIS
LACTIC-ACID BACTERIA
BACILLUS-SUBTILIS
Ciencias Biológicas
03 medical and health sciences
purl.org/becyt/ford/1.6 [https]
LACTOCOCCUS-LACTIS
030304 developmental biology
CHEDDAR CHEESE
030306 microbiology
OXALOACETATE DECARBOXYLASE
Metabolism
biology.organism_classification
Citric acid cycle
Oxaloacetate decarboxylase
chemistry
Fermentation
Citrate fermentation
biology.protein
LEUCONOSTOC-MESENTEROIDES
Calcium Citrate
Energy Metabolism
Food Science
Subjects
Details
- ISSN :
- 10985336 and 00992240
- Volume :
- 79
- Database :
- OpenAIRE
- Journal :
- Applied and Environmental Microbiology
- Accession number :
- edsair.doi.dedup.....93ad81b1bfd019a1fd270820772c9c2c
- Full Text :
- https://doi.org/10.1128/aem.00925-13