The heterotrophic bacteria derives energy from the organic compounds. They are found in abundant forms and are widely distributed. They can be either anaerobic or aerobic. These bacteria are omnipresent and can be found in soil, water, and food. They help with the recycling of natural substances.
The heterotrophic bacteria is liable for the decomposition of organic matter. They live as parasites and lead to several diseases in humans, animals, and plants. They also exist in the form of symbiont in organisms, for example, Rhizobium in root nodules of the legumes etc. Bacteria is used for creating antibiotics, curd, nitrogen-fixation, etc. Organic matter like chitin, cellulose, lignin, and keratin can be decomposed by heterotrophic bacteria.
The Various Types of Heterotrophic Bacteria
As per their food source, association with other organisms, and habitat, heterotrophic bacteria can be broadly classified in three main categories: Parasitic, Saprophytic, Symbiotic.
Parasitic Bacteria: The parasitic bacteria can also be the parasite on plants or animals. Not all the parasitic bacteria tend to be pathogenic, for instance microbial flora of the human body, presence in skin, mucous membranes, digestive tract, and other organs that coexist without harming. Various diseases can be caused by the pathogenic heterotrophic bacteria. These have different infection modes and transmission. The examples of the bacteria are as follows.
In humans: Typhoid - Salmonella Typhi, Cholera - Vibrio cholerae, Tetanus - Clostridium tetani, Lyme disease - Borrelia, Whooping cough - Bordetella pertussis, Diarrhoea - Escherichia coli, Diphtheria - Corynebacterium diphtheriae, Gonorrhoea - Neisseria gonorrhoeae, and Tuberculosis - Mycobacterium tuberculosis.
In plants: Citrus canker - Xanthomonas axonopodis, Blight of beans - Xanthomonas campestris, Crown gall - Agrobacterium tumefaciens, Granville wilt - Pseudomonas solanacearum, and Wildfire of Tobacco - Pseudomonas syringae.
Characteristics of Heterotrophic Bacteria
The bacteria mainly comprises simple cellular structure, that includes capsule, flagellum, cell wall, pili, ribosomes, cytoplasm, and chromosomes. The microorganisms can be found everywhere, in our communities and all around us. The bacteria shape varies based on the type. The length of the complete bacteria is measured only by a few micrometres.
The other structural features of Prokaryotic Microorganisms are:
It lacks a membrane-bound nucleus.
Every bacterial cell has its own plasmids that are involved in food digestion, replication etc.
It is made of single chromosome, circular-shaped DNA which is found in the cytoplasm.
The plasmids are circular, small, and have double-stranded DNA structures that are naturally found in bacterial cells.
Bacteria use both sexual as well as asexual methods for reproduction. Most of the bacteria rely on binary fission.