Question

1. Based on the following preliminary data, which organisms can you rule out? (i.e. This organism is NOT... ) Gram-positive Rods and Cocci Rods Cocci Spore-former Non-spore-former Spore-former Non-spore-former 5 um Acid-fast Not acid-fast Catalaset irregular & tetrad arrangement Catalase pairs or chain arrangement Regular Pleomorphic Group 1 Bacillus Clostridium Sporolactobacillus Group II Mycobacterium Group III Lactobacillus Listeria Kurthia Group IV Corynebacterium Propionibacterium Arthrobacter Group V Sporosarcina Group VI Micrococcus Planococcus Staphylococcus Group VII Streptococcus

Answer 1

1) This organism is not from gram positive rods as image of the organism showing coccus like shape. so the organism is not from Group I , Group II , Group III and Group IV.

2) The organism is not a spore forming gram positive cocci as thre is no spore in culture plate. so the organism is not from Group V.

3) The organism is not from catalase -ve gram positive cocci as it is showing bubble in culture plate. so the organism is not from Group VII.

conclusion: - the organism is from Group VI. the organism is catalase +ve gram positive cocci.

explanation -  If an organism can produce catalase, it will produce bubbles of oxygen when hydrogen peroxide is added to it.