Contemporary philippine arts from the regions_PPT_Module_12 [Autosaved] (1).pptx
Gram-Positive Rod-Shaped Bacteria that Produce Lactic Acid
1.
2. John Paul De Guzman
Judea Clarice Prado Reate
Irish Minor Quinday
Marilou Amos
Maria Cristina Lauderis Aglabay
Felbertine Joy Custodio
3. Gram positive
Aero tolerant anaerobes or microaerophilic
Rod-shaped
Non-spore-forming bacteria
They are a major part of the lactic acid bacteria group
(i.e. they convert sugars to lactic acid)
Produce lactic acid as the major metabolic end product of carbohydrate
fermentation, giving them the common name lactic acid bacteria (LAB)
4. Forms biofilms allowing them to persist during harsh environmental
conditions and maintain ample populations
They are usually found in decomposing plants and milk products
In humans and animals, they constitute a significant component
of the microbiota at a number of body sites
Lactobacillus exhibits a mutualistic relationship with the human body, as it
protects the host against potential invasions by pathogens, and in turn,
the host provides a source of nutrients.
5. Organisms under the order Lactobacillales are rod, spherical or
capsule-shaped usually in pairs or chains. Being gram-positive
organisms, Lactobacillales have thick peptidoglycan, ranging 20-
80 nm. Organisms have varying numbers of flagella (the long
and slender thread-like structure attached to the appendage),
which are used primarily for movement. They also possess pili,
or the short hair-like structure around their capsule, which are
used to adhere on surfaces.
6. Families under Lactobacillales are characterized by their ability
to produce lactic acid as a major by-product of glucose
metabolism.
Two Types of Metabolism in Lactobacillales
- Some species perform Homofermentative metabolism, in
which one glucose molecule is broken down into two
molecules of lactic acid exclusively.
- In Heterofermentative metabolism, glucose is broken down
into lactic acid (more than 50%), CO2, acetic and ethanol.
7. According to metabolism, LAB species can be divided into three groups:
Obligate homofermentative (group 1) including:
L. Acidophilus, L. delbrueckii, L. Salivarius
-obligate homofermentative LAB which ferment hexoses almost entirely to
lactic acid; pentoses or gluconate are not fermented.
Facultative heterofermentative (group 2) including:
L. casei, L. Curvatus, L. Plantarum, L. Sakei
-facultative heterofermentative LAB either ferment hexoses almost entirely into
lactic acid and, under glucose limiting conditions, ferment hexoses to lactic
acid, acetic acid, ethanol and formic acid; pentoses are fermented to lactic acid
and acetic acid.
8. Obligate heterofermentative (group 3) including:
L. brevis, L. buchneri, L. fermentum, L. reuteri
- obligate heterofermentative LAB which ferment hexoses to lactic acid,
CO2, acetic acid and/or ethanol; pentoses are fermented to lactic acid
and acetic acid.
9. Organisms under Lactobacillales are commonly found on the
mucous membranes of the mouth, digestive, respiratory, and
genitourinary tracts, and on the skin of man and animals—
including insects. They are also present in milk and dairy
products, in some food and plant materials, soil and fecally
contaminated water. Such environment they thrive in reflects
their respiration, for some are facultative or obligate anaerobic.
10. Organisms under Lactobacillales can produce lactic acid from glucose.
Such organisms are acidophilic, they can tolerate and grow on
environment with low pH levels.
Most of them are capable of withstanding environment with high
temperature. Researchers have unveiled that L. casei remain cultivable at
temperature of 65° C.
11.
12. They are thin, rod shaped and found in singles
rods or in small chains
Gram stain positive
They can be motile or non-motile and do not
have spores
They generally produce lactic acid mainly from
glucose fermentation
Most species are psychrophilic and
psychrotolerant (able to grow and reproduce at
temperatures between -10 to 20 °C)
Acetic acid and ethanol are also common
byproducts
They grow extremely well when heme, a blood
pigment with iron, is added to aerobic
conditions. However, they can also live in
anaerobic conditions as well making them
facultative anaerobes
13. They produce lactic acid and get their
energy from fermentation of different
hexoses
Although they are lactic acid producing
bacteria, they grow in a PH range of 7-9
They do not caused diseases
Habitat
Appear to have both the temperate and
polar aquatic environments as habitats
(live fish, marine sponges, and Arctic sea
water as well as the deep sea)
Terrestrial environment
High-pressure habitats
14. a) Stained section of a liver from a Carnobacterium
maltaromaticum-like infected lake whitefish exhibiting mild
hepatocyte degeneration due to cytoplasmic vacuolation
(H&E stain, 200 magnification).
(b) Stained section of a liver from a C. maltaromaticum-like
infected lake
whitefish exhibiting mild bile stasis (H&E stain, 400
magnification).
(c) Stained section of a normal lake whitefish swim bladder
(H&E stain,
200 magnification). (d) Stained section of a lake whitefish
swim
bladder from which a C. maltaromaticum-like bacterium was
isolated
exhibiting severe epithelial hyperplasia (H&E stain, 200
magnification)
15. Carnobacterium inhibens isolated after incubation at 37 °C for
18 h. a, b 1–2 mm diameter, grey-colored, round,
alpha-hemolytic colonies on 5% sheep blood agar. c Grey-
colored, flat colonies surrounded by greenish
discoloration around the colonies on chocolate agar. d Gram
staining of blood culture isolate of C. inhibens
depicting Gram-positive, asporogenous, lactobacillus-like rods,
100x
16. Gram-positive
Non-motile cocci
Occurring in pairs or irregular clusters, usually small
Aerobic and facultatively anaerobic
They survive heating to 60" for 30 min. and grow at
pH 9-6
The organisms are also very common in floor-dust
from on clothing, and in dust from yards and streets
Organisms of this sort are present only in very small
numbers, if at all, in the upper respiratory tract of
normal persons, and they are by no means common in
feces; may be present in rather small numbers on
normal skin
They can cause invasive infections such as urosepsis
or infective endocarditis
19. A family of Gram-positive bacteria;
produce lactic acid as the major
metabolic end product. Representative
genera include Enterococcus,
Melissococcus, Pilibacter,
Teteagenococcus and Vagococcus.
Facultative anaerobic
Currently contains 24, 938 genomes
21. ASM Journals - American Society for Microbiology
Characterization of Clinical Enterococcus faecalis Small-
Colony Variants | Journal of Clinical Microbiology
22. Gram-positive
Nonsporulating bacteria, exhibiting G + C DNA
content less than 50%
They develop in anaerobic or aerobic conditions,
and a catalase generally is not present
They are usually mesophiles, cultured at
temperatures around 30 °C
They need complex media for growth
Found in nutrient-rich habitats associated with
food, feed, plants, animals and humans
Rarely associated with pathology, but in the
presence of risk factors and underlying
conditions, they can cause infections such as
endocarditis, bacteremia, or neonatal meningitis
24. Isolation and identification of
antagonistic Lactobacillus spp. isolated
from dairy products against selected
pathogens
25. A family of Gram-positive bacteria and
characterized by spherical chain-shaped
structure. They are typically non-
motile, non-spore forming facultative
anaerobes and oxidase negative.
Representative genera include
Lactococcus, Lactovum, Streptococcus,
Floricoccus and Okadaella.
Currently contains around 50, 767
genomes
27. Lactococcus lactis – used in the
production of buttermilk and cheese
Streptococcus bovis (pathogenic) – causes
urinary tract infections, endocarditis, sepsis,
and colorectal cancer.
28. A family of LAB widely present in many
ecological niches associated with complex
microsystems. They are grouped into four
genera, Leuconostoc, Fructobacillus,
Weissella, and Oenococcus.
Found in environments with high nutrient
content, e.g., on green vegetation, roots, and
food.
Used for fermented milks, butter, and cheese
production.
They have a low acidifying capacity and are
primarily chosen for their ability to produce
typical aromas and flavors as well as inhibit
some undesirable contaminants
29. Leuconostoc
- Defined as bacteria producing lactic acid exclusively or not,
from carbohydrates fermentation.They are Gram positive,non
sporulating bacteria.
Fructobacillus
- It is classified as a fructophilic lactic acid bacterium. They are
usually found in high fructose environments such as fruits and
flowers. Their unique growth characteristics are due to their
adaptation to fructose-rich habitats.
30. Weissella
- Known as lactic acid bacteria. They are obligatory
heterofermentable and produce CO2 from carbohydrate metabolism
with either D (-) or a mixture of D (-) and L (+) lactic acid and acetic
acid as the main end product of glucose metabolism.
Oenococcus
- Most common type of lactic acid bacteria contained in wine. It
develops after the alcoholic fermentation and results in the
malolactic fermentation required to improve the quality of most
wines.
