микробиология (2ой семестр) / Биохим.идентификация

Рисунок 1

Рисунок 2

Сухая питательная среда типа Клиглера используется для идентификации энтеробактерий по способности сбраживать углеводы и продуцировать сероводород

Рисунок 3

Рисунок 4

Среда Симмонса для определения способности микроорганизмов утилизировать цитраты

Тест на индол

Рисунок 5

The tube on the left is negative and the tube on the right is a positive result.

Urea:

This test is used to detect the enzyme urease, which breaks down urea into ammonia. Ammonia is a base and thus will raise the pH of the media if it is present. This change in pH is indicated by a pH indicator called phenol red which is present in the media. A color change from yellow to bright pinkish-red is positive; lack of color change is a negative result. Inoculate the liquid media with a transfer loop.

 

Рисунок 6

The tube on the left is a positive reaction; the tube in the middle is a negative reaction and the tube on the right in an un-inoculated control.

Тест на липазу . Среда с с трибутиратом и метиленовым синим. Зона просветления-липазная активность. Positive: Serratia marcescens. Negative: Escherichia

Рисунок 7

Тест на желатиназу

The 'Serratia marcescens' on the left is positive for gelatinase production, as evidenced by the liquidation of the media.  The 'Salmonella typhimurium' on the right is negative, as evidenced by the solidity of the media.

Triple sugar Iron (TSI) - & Hydrogen sulfide production (H₂S): Looks at fermentation of glucose, lactose, and sucrose and checks if hydrogen sulfide

SLANT COLOR:	Interpretation
RED	does not ferment either lactose or sucrose
YELLOW	ferments lactose and/or sucrose

BUTT COLOR/CONDITION	Interpretation
RED	no fermentation of glucose
YELLOW	some fermentation of glucose has occurred, acid has been produced
GAS FORMED	Seen as cracks in the agar, bubbles, or the entire slant may be pushed out of the tube.  (Caution:these gassy fermenters may have bacteria close to the opening.)
BLACK	H2S has been produced

From left to right:

1. Uninoculated control

2. Red slant and red butt, no black color= no fermentation of glucose, sucrose or lactose. No Hydrogen sulfide produced

3. Red slant and black butt= no lactose or sucrose fermentation, H₂S has been produced

4. Red slant with yellow butt= no lactose or sucrose fermentation, lactose is fermented, no H₂S has been produced

5. Yellow slant, yellow butt and black coloration= Lactose, sucrose and glucose fermented, and H₂S has been produced

6. Yellow slant, yellow butt and lifting and/or cracking of media, no black coloration= Lactose, sucrose and glucose fermented, H₂S has not been produced but gas has been produced

7. Yellow slant, yellow butt and no lifting and/or cracking of media, no black coloration= Lactose, sucrose and glucose fermented, H₂S has not been produced nor has gas been produced

Catalase: 

Bubbling upon the addition of hydrogen peroxide is indicative of the presence of catalase for this organism

Окислительно-ферментативные среды

Тест на подвижность

Left tube is result for a non-motile bacterium. Right tube is the result for a motile organism.

API Test   Начало формы Конец формы Начало формы Конец формы Aseptically place the API strip into the wetted tray. This means that the strip should only be picked up by the edges; your fingers should not come into contact with the cupules. A single bacterium in a cupule will change the reading.

Начало формы

Конец формы

Using the same pipette, hydrate and inoculate each cupule with your suspension. Unless otherwise indicated, only fill each cupule to the base of the open end (the "shoe" of the cupule).

Начало формы

Конец формы

On the cupules where the code is bracketed as shown in in this picture (GEL), fill the entire cupule, including the open end.

Начало формы

Конец формы

Here is how the completed API test should look before incubation. The liquid suspension helps to hydrate the media so that it distributes evenly throughout the cupule.