Research on Brucella Abortus

By: Maharshi Patel

Introduction

• The complete name of bacteria is “Brucella Abortus”.

• It’s classification is as under. Kingdom: Bacteria Phylum: Proteobacteria Class: Alphaproteobacteria Order: Rhizobiales Family: Brucellaceae Genus: Brucella Species : Abortus.

Characteristics

• They are classified as coccobacilli which means that they are rod-shaped bacteria..

• They are small (0.5 to 0.7 by 0.6 to 1.5 µm), non-motile, non-encapsulated.

• Brucella Abortus are gram-negative bacteria.• They don’t have flagella or pili, nor do they create

capsule slime.• This pathogen is different from many in that it does

not contain any plasmids or genomic islands that relate to pathogenicity within its genome.

Unique Characteristics• Brucella Abortus is an intracellular bacteria, which means that it does not

replicate outside the host organism.• This bacterium, as an intracellular pathogen, enters phagocytes, such as

macrophages, in humans and in cows.• It attaches to the endoplasmic reticulum of these cells. • These smooth bacteria enter macrophages and then live in compartments of

vacuolar space along the ER.• Though Brucella Abortus is an intracellular bacterium it can remain alive outside

the host without replicating.

Metabolism

• This heterotrophic bacteria carries out either aerobic or anaerobic respiration because it is a facultative bacterium.

• This means that the bacteria can grow with or without oxygen present.

• In order to grow Brucella Abortus, a very complex media is required, because it is a fastidious bacteria that requires most essential nutrients to be imported into the cell from the host.

• Although it is a fastidious bacteria, Brucella Abortus does have all major biosynthetic pathways.

Disease caused

• The disease by Brucella Abortus was first discovered in soldiers who were living on the island of Malta by Dr. David Bruce, for whom the pathogen gets its name.

• It causes a disease called brucellosis.• B. Abortus was originally found in cattle and causes

problems with fetus development and viability, but this pathogen can be passed to humans.

• In these cases the most common mode of transmission is through unpasteurized milk and cheese products because the bacteria is present in the milk glands of a female cow.

Effects of Disease in Humans

• In humans the disease has both an acute and a chronic phase.• The chronic phase will last as long as the host is alive without treatment.• Acute symptoms include fever, chills, headache, backache, weakness, and

weight loss.• The chronic symptoms are usually recurring joint pain, fatigue, and

headaches.• There is an antibiotic regiment for humans who come in contact with the

disease that includes the antibiotics rifampin and doxycycline together.