What is the structure of Mycobacterium?
The cell envelope of Mtb comprises four main layers: (i) the plasma membrane or inner membrane, (ii) the peptidoglycan–arabinogalactan complex (AGP), (iii) an assymetrical outer membrane or ‘mycomembrane’, that is covalently linked to AGP through the mycolic acids, and (iv) the external capsule [22].
How is Mycobacterium tuberculosis structured?
Mycobacterium Tuberculosis has a rod-shape and its a pretty large bacteria! The length of the bacteria usually ranges from 2 to 4 micrometers and the width is somewhere between 0.2 to 0.5 micrometers. Interestingly, Mycobacterium tuberculosis is a non-motile bacteria (Todar).
What is the microscopic morphology of Mycobacterium tuberculosis?
Mycobacterium species has a specific morphology when grown in liquid medium. Mycobacterium tuberculosis complex (MTB) often exhibits serpentine cording, which is different from the dot and cross-barring morphology observed in Mycobacterium avium complex (MAC) and Mycobacterium kansasii (MK), respectively.
How would you describe Mycobacterium?
Mycobacteria are immobile, slow-growing rod-shaped, gram-positive bacteria with high genomic G+C content (61-71%). Due to their special staining characteristics under the microscope, which is mediated by mycolic acid in the cell wall, they are called acid-fast.
What are the 3 major components of the Mycobacterium cell wall structure?
The essential core cell wall structure is composed of three main components: a cross-linked polymer of peptidoglycan, a highly branched arabinogalactan polysaccharide, and long-chain mycolic acids.
Is mycobacteria Gram-positive or negative?
Gram-positive
Mycobacteria are Gram-positive, catalase positive, non-motile, non-spore forming rod-shaped bacteria (0.2–0.6 μm wide and 1.0–10 μm long). The colony morphology of mycobacteria varies with some species growing as rough or smooth colonies.
What is the shape and arrangement of Mycobacterium tuberculosis?
M. tuberculosis is a small, rod-shaped, strictly aerobic, acid-fast bacillus 1 . Like other mycobacteria, it is slow growing, resulting in more gradual development of disease when compared with other bacterial infections. Acid-fast bacilli are bacilli, which once stained, resist discoloration by acid and alcohol.
What characteristic is unique to Mycobacterium?
The distinguishing characteristic of all Mycobacterium species is that the cell wall is thicker than in many other bacteria, being hydrophobic, waxy, and rich in mycolic acids/mycolates.
What is the cellular morphology of Mycobacterium?
Table 1
| Feature | Mycobacterium | Rhodococcus |
|---|---|---|
| Cell shape | Mainly rods, sometimes branching | Scanty mycelium fragmenting into rods and cocci |
| Cell envelope | Waxy coat | Waxy coat |
| Mycolic acids | 60 – 90 carbon atoms | 32 – 66 carbon atoms |
| Growth rate (time for visible colonies) | 2 – 40 days | 1 – 3 days |
What is special about Mycobacterium cell wall?
The hallmark of mycobacteria is their unique abundance in lipid, constituting up to 40% of the dry weight of the tubercle bacillus3,4. The mycobacterial cell wall contains up to 60% of lipids, as compared with some 20% for the lipid-rich cell walls of Gram-negative microorganisms4.
What kind of cell wall does Mycobacterium have?
The mycobacterial bacillus is encompassed by a remarkably elaborate cell wall structure. The mycolyl-arabinogalactan-peptidoglycan (mAGP) complex is essential for the viability of Mycobacterium tuberculosis and maintains a robust basal structure supporting the upper “myco-membrane.” M.
Is Mycobacterium aerobic or anaerobic?
Mycobacterium is a dominant genus in the soil, and all its species are obligate aerobes. Here we show that an obligate aerobe, the soil actinomycete Mycobacterium smegmatis, adopts an anaerobe-type strategy by activating fermentative hydrogen production to adapt to hypoxia.
Which bacteria are involved in sulfolipid biosynthesis?
Genes involved in sulfolipid biosynthesis were first discovered in the purple bacterium Rhodobacter sphaeroides ( Benning and Somerville, 1992a,b) and orthologues were subsequently isolated from cyanobacteria ( Güler et al., 1996, 2000 ), plants ( Essigmann et al., 1998; Yu et al., 2002) and Chlamydomonas ( Sato et al., 2003b ).
What is the function of sulfolipids in photosynthesis?
In short, sulfolipids have been implicated in the functions of two of the core components of the photosynthetic electron transport chain and while not necessarily essential, might have a protective function when the photosynthetic apparatus is under stress.
What is Stf0 in Mycobacterium tuberculosis?
Sulfolipid-1 (SL-1) is an abundant sulfated glycolipid and potential virulence factor found in Mycobacterium tuberculosis. SL-1 consists of a trehalose-2-sulfate (T2S) disaccharide elaborated with four lipids. We identified and characterized a conserved mycobacterial sulfotransferase, Stf0, which generates the T2S moiety of SL-1.
What is the pathophysiology of Mycobacterium tuberculosis?
Mycobacterium tuberculosis, the causative agent of tuberculosis, is unique among bacterial pathogens in that it contains a wide array of complex lipids and lipoglycans on its cell wall. Among them, the sulfated glycolipid, termed sulfolipid is thought to mediate specific host pathogen interactions during infection.