Microbiology BI 121 (Serratia) PDF

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Summary

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Description

Microbiology project 1 Organism

Serratia liquefaciens 35551

Characteristics 1.0 Characteristics (2 marks) 1.1 Microscopic morphology

S. liquefaciens is a straight rod-shaped bacterium with a diameter of 0.5-0.8 μm... They are motile and contain flagella.

1.2 Colonial morphology 1.3 Staining reaction(s) 1.4 Atmospheric and nutritional requirements

Liquefaciens(serratia)593,594,601,605,666,682,800-806,807,808-811 https://www.nature.com/articles/s41598-018-33140-4 https://catalog.hardydiagnostics.com/cp_prod/Content/hugo/Serratia.htm https://microbewiki.kenyon.edu/index.php/Serratia_liquefaciens#Description_and_signifi cance https://www.mdpi.com/2075-1729/10/6/77/htm https://www-sciencedirectcom.ezcentennial.ocls.ca/science/article/pii/S0304389415302466?via%3Dihub

History:

The group of strain which was named Aerobacter liquefaciens by Grimes and Hennerty(1931) was included in genus Enterobacter. This species was then transferred to genus Serratia as Serratia liquefaciens by Bascomb et al (1971)

Taxonomy: Domain: Bacteria Phylum: Proteobacteria Class: Gammaproteobacteria Order: Enterobacteriales Family: Enterobacteriaceae Genus: Serratia

Habitat: S. liquefaciens can inhabit both aerobic and anaerobic environments. Therefore it can be found in a wide variety of environment. They are capable of colonizing on soil, water and digestive tracts of rodents, insects, fish and humans.

Cultural Characteristic: 1. Microscopic morphology : ● S. liquefaciens is a straight rod-shaped bacterium. ● They are motile and contain peritrichous flagella.

2. Colonial morphology : ● ● ● ●

Colony diameters are around 1.5-2.0mm after overnight growth on nutrient agar. They don’t have any capsule or spores Colonies often appear opaque The colony colour ranges from pink to reddish.

3. Staining reaction 4. Atmospheric requirements ● ● ● ●

They usually grow in the temperature between 28-35 degrees C. The average incubation time is between 24-28 hours Favourable pH is 5.0-9.0. Some strain of Serratia liquefaciens cells can grow in low temperature, low pressure and CO2 enriched anoxic atmosphere. ● There is no sodium ion requirement for growth in the genus

Isolation and identification(pg 801) ● Samples are inoculated on CT agar (Starret al.,1976). ● After 2-5 days, The growth is removed and tested for DNase activity. ● DNase-positive culture is then purified by streaking on TSA agar. ● Different types of polymerase chain reaction can be used to identify it. Significance(pg 803, library) ● S. liquefaciens are known to infect and cause mortality in a variety of insects which can be serious pests of crops, ornamental, and turf throughout the world. ● S. liquefaciens is known to have the capacity to decolourise azure-B dye produced by pulp and paper mill which shows the significant potential of S. liquefaciens for bioremediation of pulp and paper mill.

Recent research: 1)Biosynthesis of Heliotropin by a novel strain of Serratia Liquefaciens by Mingtao Zhao, Pu zheng, Pengcheng Chen and Siqin Liu(26 April 2017) The main objective of this research was to produce heliotropin via microbial conversion. Heliotropin is an aromatic aldehyde which is found in Vanilla, camphor woods and olive oil. With the increase in demand for flavours and fragrances the importance of finding an alternate method has also increased. In this study, it was found that ZMT-1 strain is capable of synthesizing heliotropin effectively which was obtained from the enrichment culture of soil sample and identified as Serratia Liquefaciens. The results showed that the highest heliotropin production was achieved under the optimized condition. 2)Evaluation of bioremediation potential of ligninolytic Serratia liquefaciens for detoxification of pulp and paper mill effluent.by Izhar Haq, Sharad Kumar, Vineeta Kumari, Sudheer Kumar Singh, Abhay Raj The objective of this study was to find out more about the bacteria which effectively reduced the pollution load of pulp and paper mill effluent. The bacteria were found to be S. liquefaciens. It showed a significant reduction in toxicity of the observed effluent. The study showed us that the isolated strain was capable of degrading lignin from the effluent, detoxifying and pollutant reduction which proves it’s credibility as a potential candidate for further treatment studies....