The document discusses the characteristics and classification of the bacteria Yersinia, specifically focusing on Yersinia pestis, the causative agent of the plague. Yersinia is classified within the family Enterobacteriaceae and includes three major species: Y. pestis, Y. enterocolitica, and Y. pseudotuberculosis. The historical context of Yersinia pestis's classification and discovery is also provided.

2. Presented by
RAAZIA AKRAM

3. Characteristics
Gram-negative,
ovoid or rod-shaped
2.5-3.0 mm in diameter
at temperatures as low as 1-4°C
Aerobes or facultative anaerobes
Oxidase-, catalase+,
Infectious is more in warmth season
,

4. Kingdom: Bacteria
Phylum: Proteobacteria
Class: Gammaproteobacteria
Order: Enterobacteriales
Family: Enterobacteriaceae
Genus: Yesinia
SCIENTIFIC CLASSIFICATION

5. Y. pestis, the first known species, was identified in
1894 by A.E.J. Yersin and Kitasato Shibasaburō,
as Pasteurella pestis by Lehmann and Neumann in
1896
In 1944, van Loghem reclassified the species P.
pestis and P. rondentium into a new genus, Yersinia.
Following the introduction of the bacteriological
code, it was accepted as valid in 1980.
HISTORY

6. About 11 species are known but 3
are most important
Y.pestis
Y.enterocolitica
Y.pseudotubercolosis
SPECIES

7. YERSINIA PESTIS

19. YERSINIA ENTEROCOLOTICA
AND YERSINIA
PSEUDOTUBERCOLOSIS