Robert Koch

Robert Koch (1843-1910)

Father of Bioteriology, father of microbial techniques

Father of medical microbiology.

Contributions are-

  1. Perfected bacteriology techniques and introduced method for isolation of pure strains of bacteria.
  2. Introduce methods of obtaining bacteria in pure culture using solid media. Example; Agar
  3. Introducing staining techniques
  4. Proved role of bacteria in causing disease.
  5. First to use hanging drop method by studying bacterial motility.
  6. Koch’s postulates (1876) and Koch phenomenon

Koch’s Postulates or Koch’s Laws

According to Koch’postulates a microorganism can accepted as the causative agent of an infectious diseases only if the following conditions are satisfied –

  1. Postulates I (Association)

The microorganism must be found in abundance in all organism suffering from disease. (should be regularly found in the lesions of disease).

  1. Postulate II (Isolation)

The organism must be isolated from the diseased animal and grown in pure culture. (should possible to isolate the organism in pure culture from the lesions.)

  1. Postulate III (Inoculation)

The isolated microorganism should cause the same disease when inoculated into healthy animal. ( Inoculation of pure culture into suitable laboratory animal should produce the lesion of diseases.

  1. Postulate IV ( Reisolation)

The microorganism must be reisolated from the inoculated host and identify as being identical to original specific causative agent.

( It should be possible to reisolate the organism in pure culture from the lesions produce in the experimental animals.

Robert koch criteria for providing the causal relationship between microorganism and a specific disease are known as Koch’s postulates.

Koch’s phenomenon (1890)

Koch observed that a guinea pig already infected with the bacillus responded with an exaggerated response, when injected with the tubercle bacillus or its protein.

This Hypersensitivity reaction is known as koch’s phenomenon.