Summary Microbiology and Immunology Brucella Questions With 100% Verified Answers

What is the host for Brucella melitensis? - correct answer Goats What is the host for Brucella abortus? - correct answer Cows; it causes abortion in cows What is the host for B. suis? - correct answer pigs What is the host for B. ovis? - correct answer Sheep What is the host for B. canis? - correct answer dogs What is the host for B. neotomae? - correct answer Desert wood rat What species are most pathogenic for humans? - correct answer B. melitensis, B. abortus, and B. suis What species are of low pathogenicity for humans? - correct answer B. canis, B. ovis, and B. neotomae General properties of Brucella species: - correct answer coccobacilli, coccoid, and rod-shaped. no capsules non-motile Brucella respires - correct answer aerobically Catalase and oxidase - correct answer positive Negative for: - correct answer acid production, gelatinase, VP, methyl red, and indole Positive for: - correct answer urease The cell wall for Brucella is _______ and contains ______ - correct answer MESO-DAP; LPS What is unconventional about the LPS? - correct answer It's structure because it has low endotoxicity. Thus, it is hidden from the immune system Two types of LPS - correct answer Smooth phase LPS Rough phase LPS Smooth phase LPS - correct answer -More virulent -Has a long O chain Rough phase LPS - correct answer -More sensitive to complement system -Has short O chain Which species occur in rough phase LPS? - correct answer B. ovis and B. canis Species that occur in smooth phase LPS? - correct answer B. melitensis, B. abortus, B. suis, and B. neotomae The long O-polysaccharide of the short LPS contain two main antigens: - correct answer A and M There are three phenotypes of antigens possible: - correct answer B. abortus (A+M-), B. melitensis (A-M+), and B. suis (A+M+) The genome of Brucella species contains what? - correct answer 2 circular chromosomes An exception is B. suis biovar 3, which contains - correct answer 1 circular chromosomes Does any Brucella species have plasmids? - correct answer NO Are Brucella species commensal or free-living? - correct answer NO What disease caused by Brucella species is typically occupational? - correct answer Brucellosis How are Brucellae transmitted? - correct answer Ingestion of meats or dairy products Direct contact with infected animals Inhalation of aerosolized organisms The most commonly reported lab infection - correct answer Brucellosis Brucella organisms are defined as - correct answer facultative intra-cellular pathogens To defeat innate and adaptive immunity, Brucella - correct answer lowers it stimulatory activity and toxicity for cells