Random Selection Of Micro-Organisms ; 1) Haloquadratum Walsbyi :

Today ,

Concept Of Microbiology 

Taking you to on the tour of Random Selection of Microorganisms and their effects when ever they are presence in the Enivornment and their ability and impacts on our day today life ...

So what you are you waiting for 

Lets Dive in .....🌊

1) Haloqaudratum walsbyi (Halophile) :

Introduction :

Salt has been historically used for preventing decay and preserving food, as many microbes 

are unable to survive under high salinities. Despite this, several organisms – also known as halophiles (from the greek “salt-loving”) – are specifically adapted and thrive under such 

conditions. The study of their biodiversity provides us important new biomolecules and 

biotechnological applications, which are vital resources for the Bioeconomy. Equally important, research on halophiles offers new insights on Life’s resilience, and its possible existence outside our planet.

2) Scientific information :

 Higher order taxanomy : ✓

Cellular organisms : Archaea : 

Class  : Euryarchaeota : Halobacteria;

Order  : Halobacteriales  ; 

Family : Halobacteriaceae ;

Genus  : Haloquadratum

Genera : walsbyi

i) The square halophilic archaeon Haloquadratum walsbyi was first discovered by A.E. Walsby in 1980. First found in water from a salt pool near the Red Sea, Haloquadratum walsbyi was soon found in many salt lakes around the world, making it an archaeon of specific interest because of this abundance in hypersaline ecosystems, which suggests that it plays an important ecological role. A.E. Walsby detected Haloquadratum walsbyi by "conventional microscopy in brine samples collected from a salt crust forming the surface of a hypersaline pool on the Sinai Peninsula".

ii) The cells of "Walsby's square archaeon" possess a unique square-like shape, unlike the spherical or cylindrical shape of many organisms. Easily recognizable for its perfect square morphology, Haloquadratum walsbyi has sharp edges and acute straight corners.

iii) Despite their abundance in salt lakes around the world, cultivation of Haloquadratum walsbyi has been very difficult, and it has been marked an unculturable organism. In "Isolation and cultivation of Walsby's square archaon," the first cultivation of the organism is discussed.

iv) It is important for this organism to be studied because of its halophilicity which suggests that Haloquadratum walsbyi plays an important ecological role in high-salt content habitats. The genome sequence gives insight in the molecular, ecological & physiological properties of the organism, including its square shape and its ability to survive in the hypersaline environments it is found in and the high UV radiation it is exposed to.

v) Additionally, studying the genome sequence might enable us to understand the metabolic properties which allow Haloquadratum walsbyi to live in such an environment and which initially made the organism difficult to cultivate.

3) Ecology : 

vi) Haloquadratum walsbyi was first collected by Anthony Walsby from hypersaline waters in the south of Sinai, but they are found in hypersaline waters all over the world. 

vii) Ecosystems (both natural and man-made) in which sea water evaporates cause the concentration and precipitation of the compounds calcium carbonate and calcium sulphate. This leaves behind a hypersaline brine that is rich in sodium chloride. 

viii) These crystalliser ponds further evaporate and concentrate the brines, causing the precipitation of halite (sodium chloride). Dense magnesium chloride brine then develops, but at the last stage of the formation of halite, Haloquadratum walsbyi is seen dominating the ponds. 

ix) This occurs before the magnesium chloride brines become sterile. At this point, Haloquadratum walsbyi constitutes up to 80% of the microbial biomass.

x) The fact that Haloquadratum walsbyi is found in such environments (and thrives here) and cannot be cultivated unless in medium that contains a high molarity of MgCl and NaCl indicates its status as one of the most halophilic organisms.

4) Pathology and Antibiotic Resistance :

😳It will be surprizingly informative organism regarding pathogenisity.... 

How ? 

see the below information,👇

xi) Nothing was found about how this organism causes disease, although it was found that H.walsbyi have sensitivity and resistance to multiple antibiotics. 

xii) It is sensitive to the following antibiotics : “anisomycin, choloramphenicol, erythromycin, novobiocin, rifampicin, simvastatin, and tetracycline”

xiii) It is resistant to the following antibiotics : ampicillin, bacitracin, cycloheximide, kanamycin, mycostatin, neomycin, and streptomycin”.

5)Cell structure & metabolism :

xiv) The very thin and flat Haloquadratum walsbyi cells measure between 1 to 5 micrometers in thickness and have a unique square-like shape. They form sheets of 2D arrays of 10 or more cells.

xv) Its surface area is very large compared to its volume due to this structure, which is thought to be helpful in nutrient exchange with the environment.Accordingly to Walsby,

xvi) “its shape is probably determined by the pattern in which the cell envelope particles assemble.”

xvii) The cells are very fragile and when in sheets, contacts between cells are easily broken. The gas vesicles within Haloquadratum walsbyi are easily collapsed even by gentle pressure. 

xviii) Its cells stained Gram-negative and were found to grow optimally in media with 18% salts around neutral pH (6.5-7.0). Its optimum growth temperature was found to be 45 degrees Celsius and its minimum growth temperature at 25-30° Celsius.

xix) Although it was found to be non-motile, another feature of H.walsbyi (which might contribute to its ability to control its location) is the abundance of intracellular refractile bodies, which were identified as gas vesicles. These gas vesicles were also found to be easily collapsed by gentle pressure. 

xx) The production of these gas vesicles are thought to provide H.walsbyi with control over its location in its habitat,as suggested by Legault et al. 

PHA storage granules have also been found in H.walsbyi.

xxi) Haloquadratum walsbyi are aerobic heterotrophs, which only use oxygen as a final electron acceptor and can neither use nitrate nor DMSO as alternative acceptors nor grow anaerobically using L-arginine.

xx) It was found that H.walsbyi grows best on pyruvate as its sole carbon source. H.walsbyi did not produce acid from carbohydrate utilization and was found to not produce beta-galactosidase enzyme.

6)Shocking Results :

Though this Archae do not causes any infection nor disease but still shows activity againts antibiotics while stimulating it.

Nothing was found about how this organism causes disease, although it was found that H.walsbyi have sensitivity and resistance to multiple antibiotics.