Is Lactococcus lactis a facultative anaerobe?

Lactococcus lactis, a facultative anaerobic lactic acid bacterium, is known to have an increased growth yield when grown aerobically in the presence of heme. Lactococcus lactis has a long history of use in the production of fermented dairy products, such as cheese and buttermilk, under mainly anaerobic conditions.

Does Lactococcus lactis ferment galactose?

We found that galactose in lactose-grown cultures was excreted and consumed after the lactose depletion as long as no inhibition by the low pH was present. Galactose, excreted or externally added is shown to be essential to produce a Lactococcus lactis subsp.

What type of media does Lactococcus lactis grow in?

When Lactococcus lactis was grown in various complex or synthetic media, the fermentation of glucose remained homolactic whatever the medium used, with a global carbon balance of about 87%.

What does Lactococcus lactis ferment?

Lactococcus lactis is a microbe classified informally as a Lactic Acid Bacterium because it ferments milk sugar (lactose) to lactic acid. Lactococci are typically spherical or ovoid cells, about 1.2µm by 1.5µm, occurring in pairs and short chains.

Is Lactococcus lactis Gram positive or negative?

Lactic Acid Bacteria | Lactococcus lactis They are Gram-positive, catalase-negative, facultatively anaerobic, nonmotile, and non-spore-forming.

Is Lactococcus lactis citrate-positive or negative?

Acetoin Fermentation by Citrate-Positive Lactococcus lactis subsp.

Does Lactococcus lactis ferment glucose?

During L. lactis fermentation, glucose is metabolized to form mainly lactic acid, and the final pH is ∼4.5.

Can Lactococcus ferment glucose?

Lactococcus constitutes one of the several genera forming the LAB family. This genus is a homofermenter that ferments sugars, releasing only one by-product, lactic acid.

Is Lactococcus Gram-positive?

In terms of cell morphology, lactococci have spherical or ovoid-shaped cells and occur singly or in chains (Figure 1). They are Gram-positive, catalase-negative, facultatively anaerobic, nonmotile, and non-spore-forming.

Is Lactococcus lactis fastidious?

The lactococci are nutritionally fastidious organisms. In nature, they most commonly inhabit environments rich in carbon and nitrogen sources, such as raw milk and plant material. During dairy fermentations, the growth medium for L. lactis is milk.

Is Lactococcus Gram-positive or negative?

Lactic Acid Bacteria | Lactococcus lactis In terms of cell morphology, lactococci have spherical or ovoid-shaped cells and occur singly or in chains (Figure 1). They are Gram-positive, catalase-negative, facultatively anaerobic, nonmotile, and non-spore-forming.

Is Lactococcus lactis prokaryotic or eukaryotic?

Lactococcus
Lactococcus lactis
Scientific classification
Domain:	Bacteria
Phylum:	“Firmicutes”

What is the application of Lactococcus lactis in biotechnology?

Application to Biotechnology. Lactococcus lactis specializes in lactate dehydrogenase excreting lactic acid, which is used to preserve food and extend food shelf life. Dairy industries continue to improve the activities and effectiveness of L. lactis by manipulating its environment and cell behavior.

What is the main metabolism of lactose?

The main metabolism of L. lactis is through the anaerobic pathway, fermentation, which produces lactic acid from the available carbohydrates and is used for industrial food production. The carbon sources that L. lactis draws from include fructose, galactose, glucosamine, glucose, lactose, maltose, mannitol, mannose, ribose, sucrose and trehalose.

What are the genes of Lactococcus lactis?

The remaining 15.7% of the genes are unidentified proteins that may be unique to the Lactococcus. The DNA replication initiation genes in L. lactis includes dnaB, dnaD, and dnaI; in addition, there are two DNA polymerase III encoded by the polC and dnaE genome.

Is Lactococcus lactis a Gram positive cell factory?

D’Souza R, Pandeya D, Hong S. Review: Lactococcus lactis: an efficient Gram positive cell factory for the production and secretion of recombinant protein. Biomed Res. 2012;23:1–7.