MICROBIAL INTERACTION PPT/ MICROBIAL INTERACTION AND THEIR TYPES // PLANT MICROBE INTERACTION // SYMBIOTIC RELATION SHIP ETC

Microbial interaction
Microorganisms interacts with each other and can be physically associated with another organisms in a variety of ways.
One organism can be located on the surface of another organism as an ectobiont or located within another organism as endobiont.
Microbial interaction may be positive such as mutualism, proto-cooperation, commensalism or may be negative such as parasitism, predation or competition
Types of microbial interaction
Positive interaction: mutualism, proto-cooperation, commensalism
Negative interaction: Ammensalism (antagonism), parasitism, predation, competition
I. Mutualism:
It is defined as the relationship in which each organism in interaction gets benefits from association. It is an obligatory relationship in which mutualist and host are metabolically dependent on each other.
Mutualistic relationship is very specific where one member of association cannot be replaced by another species.
Mutualism require close physical contact between interacting organisms.
Relationship of mutualism allows organisms to exist in habitat that could not occupied by either species alone.
Mutualistic relationship between organisms allows them to act as a single organism.
Examples of mutualism:

i. Lichens:
Lichens are excellent example of mutualism.
They are the association of specific fungi and certain genus of algae. In lichen, fungal partner is called mycobiont and algal partner is called
II. Syntrophism:
It is an association in which the growth of one organism either depends on or improved by the substrate provided by another organism.
In syntrophism both organism in association gets benefits.
Compound A
Utilized by population 1
Compound B
Utilized by population 2
Compound C
utilized by both Population 1+2
Products
In this theoretical example of syntrophism, population 1 is able to utilize and metabolize compound A, forming compound B but cannot metabolize beyond compound B without co-operation of population 2. Population 2is unable to utilize compound A but it can metabolize compound B forming compound C. Then both population 1 and 2 are able to carry out metabolic reaction which leads to formation of end product that neither population could produce alone.
Examples of syntrophism:


i. Methanogenic ecosystem in sludge digester
Methane produced by methanogenic bacteria depends upon interspecies hydrogen transfer by other fermentative bacteria.
Anaerobic fermentative bacteria generate CO2 and H2 utilizing carbohydrates which is then utilized by methanogenic bacteria (Methanobacter) to produce methane.
ii. Lactobacillus arobinosus and Enterococcus faecalis:
In the minimal media, Lactobacillus arobinosus and Enterococcus faecalis are able to grow together but not alone.
The synergistic relationship between E. faecalis and L. arobinosus occurs in which E. faecalis require folic acid

1. Microbial Interactions Microbiology Assignment Submitted by : ABHISHEK SONI B.Sc. 2 st Sem Microbiology Submitted to : Proff : Dr . Kavita Singh Chaudhary Head of deparment of Botany Govt. P.G. College Noida GOVT. P.G. GOLLEGE NOIDA SEC-39

2. Contents : Introduction History Difference between Symbiosis & Mutualism Types of Microbial interaction 1. Positive 2. Negative Conclusion

3. Difference between symbiosis & mutualism Ecologist sometimes use the term “ mutualism” and symbiosis interchangeably. The word symbiosis literally means “ living together ” Symbiosis is an ecological interaction b/w at least two species (partners) where there is a persistent contact between the partners. Mutualism is an ecological interaction b/w at least two species( partners) where both partner benefit from the relationship. All mutual relationship are symbiotic relationships, but not all symbiotic relationships are mutual relationships .

4. Introduction : Microbial interactions are  crucial for a successful establishment and maintenance of a microbial population . These interactions occur by the environmental recognition followed by transference of molecular and genetic information that include many mechanisms and classes of molecules Biological interactions are the effects that the organism in a community have on one another. There are completely different kinds of microbial interactions which incorporates interaction with different microbes. Plant-Germ microbes promoting plant growth, interactions with animals, interaction with humans, interaction with water etc. Microbial interactions are ubiquitous , diverse, critically important in function of any biological community. Most Common Cooperative interactions seen in microbial system are mutually beneficial . The interaction between two populations are classified according to whether both populations are and one of them get benefit from the associations, or one or both populations are negatively affected.

5. History: In 1879, de Bary Coined the Term Symbiosis to describe any situation where two different organism live together. In 1964, Hamilton Described Interaction as Indirect Interaction in 1971, Odom Divided all Symbiotic Relationship In 2 Groups : 1. Positive 2. Negative

6. Types of Interaction :

7. Positive interaction : 1. Mutualism : It is defined as the relationship in which each organism in interaction gets benefits from the associations . It is an obligatory relationship in which mutualist and host are metabolically dependent on each other. A Mutualistic relationship is very specific where one member of association cannot be replaced by another species. Mutualism Require close physical contact b/w interacting organism . The mutualistic relationship b/w organism allows them to act as a single organism. Example : - Lichens , Rhiobium – legume association, Mycoorrhizae , Herbivore-microbial interaction.

8. Cont …... 2. Syntrophism : it is an association in which the growth of one organism either depends on or improved by substrate provided by another organism. In s ynotrophism both organism in association get to benefit from each other. 1. Methanogenic ecosystem in sludge digester : Methane Produced by methanogenic bacteria depends upon interspecies hydrogen transfer by other fermentative bacteria . Anaerobic fermentative bacteria generates CO2 and H2 Utilizing carbohydrates and then utilized by methanogenic bacteria ( methanobactor )to produce methane. 2. Lactobacillus Arabinosus and Enterococcus faecalis : In the minimal media, lactobacillus arobinosus and enterococcus faecalis are able to grow together but not alone. the Synergistic relationship b/w E. faecalis & L. arobinosus occurs in which E.faecalis require folic acid which produced by L. arobinosus and in turn lactobacillus require phenylalanine which produced Enterococcus faecalis .

9. Cont …. 3.Proto- Cooperation : It is a relationship in which an organism in an association is mutually benefited with each other. This interaction is similar to mutualism but the relationships b/w the organism is proto-cooperation. Examples of Proto-Cooperation : association of desulfovibrio and chromatin. interaction b/w N2 – Fixing bacteria & cellulolytic Bacteria such as Cellulomonas . 4. Commensalism : it is a relationship in which one organism (commensal) in the association is benefited while another organism (host) of the association is neither benefited nor harmed . it is a unidirectional association and if the commensal is separated from the host, it can survive Examples :  lichens, mosses, and some fungi may grow on trees without harming them. association of Nitrosomonas (Host) and Nitrobacter (commensal) in Nitrification

10. Negative Interaction : 1.Ammensalism (Antagonism) : When one microbial population produces substances that are inhibitory to other microbial population then the inter-population relationship is kwon as ammensalism or antagonism. it is negative relationship. The first population which produces inhibitory substances are unaffected or may gain competition and survive in the habitat while other population get inhibited. This chemical inhibition is known as antibiosis . Examples of Ammensalism : lactic acid produced by many normal floras in vaginal tract is inhibitory to many pathogenic organism such as candida albicans . Skin normal Flora : fatty acid produced by skin flora inhibits many pathogenic in the skin.

11. Cont … P arasitism : It is a relationship in which one population (parasite) get benefited and derive its nutrition from other population (host) in the association which is harmed . the host parasite relationship is characterized by a relatively long period of contact which may be physical or metabolic. Some parasite lives outside the host cell, known as ectoparasite while other parasite lives inside the host cell known as endoparasite . Examples of Parasitism : 1. Viruses : Viruses are an obligate intracellular parasite that exhibits great host specificity. There are many viruses that parasite to bacteria (bacteriophage ), fungi, algae, protozoa etc. 2. Bdellovibrio : Bdellavibrio is ectoparasite to many gram negative bacteria.

12. Cont …. 3. Predation : it is a widespread phenomenon when one organism(predator) attack other organism (prey). Prey can larger or smaller than predator and this normally results in the death of the prey. Normally Predator – Prey interaction is of short duration. Examples of Predation : 1. Protozoan Bacteria in soil : Many protozoans can feed on various bacterial populations which help to maintain the count of the soil bacteria at optimum level. 2. Bdellovibrio , vamparococcus , Daptobactor are Examples of Predator bacteria that can feed a wide range of bacterial populations.

13. Cont …. Competition : C ompetition represents a negative relationship b/w two microbial population in which both populations are adversely affected with respect to their survival and growth. Competition occurs when both population use same resources such as same space, same nutrition so microbial population achieves lower maximum density or growth rate Microbial populations competes of any growth-limiting resources such as carbon source , nitrogen , phosphorus , vitamins growth factor etc. Competition inhibit both populations from occupying exactly the same ecological niche because one will win the competition and other is eliminated. Examples of competition: E. Coli & Coliform . Azobactor & cellulomonas . Competition b/w paramecium cadatum & paramecium Aurelia.

14. Conclusion : Microorganism engage in a variety of social interactions, including cooperation's. The role of microbes in plant growth, nutrient availability, disease resistance, yields and quality of medicinal compound is demonstrated in medicinal plants. There are increasing interests in the research of the interactions b/w medicinal plant and their rhizosphere microbes for improvement of medicinal plants.

15. THANK YOU !!!! CONTENT PREPARED BY : ABHISHEK SONI B.sc Micro Biology Govt. PG College Noida