Lactococcus lactis: Difference between revisions

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{{subpages}}
{{CZ:Biol_201:_General_Microbiology/EZnotice}}
{{Taxobox
| color = yellow
| name =  "Lactococcus lactis"
| image =
| regnum = Bacteria
| phylum = Firmicutes
| classis = Bacilli
| ordo =  Lactobacillales
| familia =Streptococcaceae
| genus =  Lactococcus
| species = L. lactis
| binomial = ''Lactococcus lactis''
| binomial_authority = 
}}
==Description and signifigance==
Lactococcus Lactis" is a non pathogenic,Gram-positive bacteria known as one of the most important microbes in dairy food production. Lactococci are immotile, nonsporelating, and are usually spherical or ovoid cells. Lactococci group in pairs or short chains with a length of about 1.2µm by 1.5µm. L. Lactis is usually found in milk and is the starter culture for the production of fermented dairy products such as cheese and yogurt. Lactococcus is considered a oportunistic pathogen because of its ability to produce lactic acid. Lactic acid produced by the the microbe curdles the milk which seperates into curds, inturn are used to produce cheese and whey.The lactic acid produced by the bacterium also lowers the pH of the product and preserves it from the growth by unwanted bacteria and molds, meanwhile other metabolic products and enzymes produced by Lactococcus lactis are responsible for the aromas and flavors of other distinguishable cheeses. Lactococcus lactis has two subspecies, Lactococcus lactis subsp. lactis and subsp. cremoris, both are used in cheese production.These organisms were originally classified under the genus Streptococcus, but in 1985, it was assigned to the current genus.
==Genome structure==
    Extensive research has been attributed to understanding the genome and physiology of this bacterium. The understanding of this bacterium is a key factor in improving the mas.
==Cell structure and metabolism==
==Cell structure and metabolism==
Lactococcus lactis functions through both aerobic and anaerobic metabolic pathways. The primitive source of energy is produced anaerobicly, which results in the accumulation of lactic acid. the deprivation of oxygen leads the glycolysis process to breakdown carbohydratesinto pryvate which then convert into lactic acid. this process is only possible through the production of the lactate dehydrogenase enzyme and NAD. Lactate is transported to the median which causes the efflux of protons resulting in the appropriate membrane potential for energy production. The lactic acid produced is used for food production.
Lactococcus lactis functions through both aerobic and anaerobic metabolic pathways. The primitive source of energy is produced anaerobicly, which results in the accumulation of lactic acid. the deprivation of oxygen leads the glycolysis process to breakdown carbohydratesinto pryvate which then convert into lactic acid. this process is only possible through the production of the lactate dehydrogenase enzyme and NAD. Lactate is transported to the median which causes the efflux of protons resulting in the appropriate membrane potential for energy production. The lactic acid produced is used for food production.
     Aerobic respiration is also used as a supplemental metabolic process. When oxygen and a heme source is present new traits are observed such as increased growth index, resistance to oxidative and acid stress, and  long-termed endurance at low temperatures. Along with heme source, the presence of membrane bound NADH dehydrogenase oxidizes NADH and increases the cell growth and production of proteins and vitamins.
     Aerobic respiration is also used as a supplemental metabolic process. When oxygen and a heme source is present new traits are observed such as increased growth index, resistance to oxidative and acid stress, and  long-termed endurance at low temperatures. Along with heme source, the presence of membrane bound NADH dehydrogenase oxidizes NADH and increases the cell growth and production of proteins and vitamins.
==Ecology==
==Pathology==
Lactococcus lactis is nonpathogenic bacteria.
==Application to Biotechnology==
==Current Research==
==References==
==New section==

Revision as of 15:12, 20 April 2009

Cell structure and metabolism

Lactococcus lactis functions through both aerobic and anaerobic metabolic pathways. The primitive source of energy is produced anaerobicly, which results in the accumulation of lactic acid. the deprivation of oxygen leads the glycolysis process to breakdown carbohydratesinto pryvate which then convert into lactic acid. this process is only possible through the production of the lactate dehydrogenase enzyme and NAD. Lactate is transported to the median which causes the efflux of protons resulting in the appropriate membrane potential for energy production. The lactic acid produced is used for food production.

    Aerobic respiration is also used as a supplemental metabolic process. When oxygen and a heme source is present new traits are observed such as increased growth index, resistance to oxidative and acid stress, and  long-termed endurance at low temperatures. Along with heme source, the presence of membrane bound NADH dehydrogenase oxidizes NADH and increases the cell growth and production of proteins and vitamins.