1. Complete identification of Unknown No. 2, if necessary.

2. Continue identification of Unknown No. 3.

1. Complete the identification of Unknown No. 2, if you did not complete it in Laboratory 7; turn in identification sheet (from page 6-8) to your instructor.
   
2. Examine your streak plates carefully; record results; select well-isolated colonies of representative types for preparation of Gram stains; and compare to results from previous laboratories.
3. Laboratory 7: Continuation and Completion of Unknown No. 3-

Gram–positive organisms-

complete identification of this unknown

Gram-negative organisms

Reading of the Crystal Enteric ID System

Calculation of the Crystal Profile Code Number

4. Consult an instructor if you are concerned that your Unknown #3 will not be identified by Lab # 9.

1. Read the Crystal panels after the recommended incubation period. All panels should be read upside-down (larger windows up; label facing down) using the X-ray viewers in the laboratory. Refer to the Color Reaction Chart for an interpretation of the reactions.
   
2. Record the results on the Crystal Results Pad.
3. Calculate the Crystal Profile Number as follows (refer to example below): Each test result that is scored positive is given a value of 4, 2, or 1, corresponding to the row where the test is located. A value of 0 (zero) is given to any negative result. The numbers (values) resulting from each positive reaction in each column is then added together. A 10-digit number is generated—this is the Crystal Profile Number

Example:	A	B	C	D	E	F	G	H	I	J
4	+	+	+	-	-	+	+	-	+	-
2	-	-	+	-	+	-	-	+	+	-
1	+	-	-	-	-	-	-	+	+	+
Profile	5	4	6	0	2	4	4	3	7	1

 

4. Identify your Gram-negative organism from Unknown #3 using the Profile Number and the Crystal Code Book.

1. Gram stain results:
   
   

 

2. Media inoculated for isolation and plate observations:
   

 

 

 

3. Biochemical tests performed and results:

 

 

 

 

 

 

 

 

 

 

 

4. Definitive identification:

 

 

---

/Total points (0.5 point for each organism for a total of 1.0 point)

Unknown No. 3-2 Specimen I.D. ________

 

 

 

Name _____________________________________ Date___________________

Results Sheet for Unknown #3

 

5. Gram stain results:
   
   

 

6. Media inoculated for isolation and plate observations:

 

 

 

 

7. Biochemical tests performed and results:

 

 

 

 

 

 

 

 

 

 

 

 

 

8. Definitive identification: