Lab 9 Notebook
BS09 Unknown Pathogen Analysis
Objective: To identify an unknown pathogen(s) based on the given assays developed during the
course.
Notes:
Two samples from the hospital were brought to your lab for diagnosis. After
culturing the samples on the LB agar plates another co-worker began the
analysis. However, due to an emergency your co-worker has left the remaining
work to you. Before leaving your co-worker informs you the 2 liquid culture
samples were accidentally combined before the Gram stain was started.
However, the 2 cultures remain separated on the LB plates for future tests.
Goal: to correctly identify the 2 pathogens.
Gram stain: a co-culture (more than one culture):
o Purple, gram-positive (spherical) clusters
o Pink, gram-negative bacillus (rods)
MacConkey Plates: used as a selective media, only gram-negative bacteria will grow
o Culture A: no growth observed because MacConkey plates are for gram negative
specific bacteria. Gram-positive because growth was not observed. Must be
cocci.
o Culture B: shows growth, pink in color (lactose-fermenting organism), gram-
negative (bacillus or rod-shaped bacteria)
o
o
This study source was downloaded by 100000829684747 from CourseHero.com on 03-18-2022 21:54:45 GMT -05:00
https://www.coursehero.com/file/102330869/Lab-9-Notebookdocx/
BS09 Unknown Pathogen Analysis
Objective: To identify an unknown pathogen(s) based on the given assays developed during the
course.
Notes:
Two samples from the hospital were brought to your lab for diagnosis. After
culturing the samples on the LB agar plates another co-worker began the
analysis. However, due to an emergency your co-worker has left the remaining
work to you. Before leaving your co-worker informs you the 2 liquid culture
samples were accidentally combined before the Gram stain was started.
However, the 2 cultures remain separated on the LB plates for future tests.
Goal: to correctly identify the 2 pathogens.
Gram stain: a co-culture (more than one culture):
o Purple, gram-positive (spherical) clusters
o Pink, gram-negative bacillus (rods)
MacConkey Plates: used as a selective media, only gram-negative bacteria will grow
o Culture A: no growth observed because MacConkey plates are for gram negative
specific bacteria. Gram-positive because growth was not observed. Must be
cocci.
o Culture B: shows growth, pink in color (lactose-fermenting organism), gram-
negative (bacillus or rod-shaped bacteria)
o
o
This study source was downloaded by 100000829684747 from CourseHero.com on 03-18-2022 21:54:45 GMT -05:00
https://www.coursehero.com/file/102330869/Lab-9-Notebookdocx/
