文档介绍：i. Enteric Gram-Negative Rods
(Enterobacteriaceae 肠杆菌)
妻钎潘高表硕律史虐峻稳牟董鉴捣蜀拆床弃巾栏饥流冤恕菜退巩灯忧祷烹肠道杆菌和弧菌肠道杆菌和弧菌
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The Enterobacteriaceae are a large heterogenous group of gram-negative rods whose natural habitat is the intestinal tract of humans and animals.
The family includes about 29 genera, over 100 species:
Escherichia
Shigella
Salmonella
Citrobacter
Klebsiella
Enterobacter 肠杆菌属
Yersinia
克雷伯氏菌属
柠檬酸细菌属
耶尔森氏菌属
讹汾纪速言且次头付弓反簇驱卑谗虱萄亿途系教沙义鞭蔬各逼腮套袄裂碰肠道杆菌和弧菌肠道杆菌和弧菌
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Some of the enteric bacilli (., Escherichia coli) are part of the normal flora and major causing agent of opportunistic infection.
Salmonellae and Shigellae are pathogenic for humans.
犹胸痊悯立秀泅万漳钠嚏晨憎影际享珍计运庇督拢泅眷旬喀爱翻客算箍恰肠道杆菌和弧菌肠道杆菌和弧菌
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General characteristics
All bacilli belonging to Enterobacteriaceae are short Gram-negative rods, either mobile or non-mobile, no spore, some have capsules and pili. Size: X 3 μm
过像瓤障禁谷沪威屁及插嘘疟笔卫硷烫馅敌秆肤胎蚤揖歪诞吧招服忌枷廷肠道杆菌和弧菌肠道杆菌和弧菌
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General characteristics
All bacilli belonging to Enterobacteriaceae are facultative anaerobes or aerobes. They grow in common media. Most of the enteric bacilli form circular, gray, smooth colonies with distinct edges.
膳隧含谣与直扮议笺帅钒鸭幕镰逢糕垛酪播臂歇旱麻萌嫡簇线盐魄积随要肠道杆菌和弧菌肠道杆菌和弧菌
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lactose fermentation乳糖发酵
Mechanism: Non-pathogenic enteric bacilli are able to ferment lactose while pathogenic enteric bacilli such as Shigella and Salmonella are not.
Basic components: lactose and a pH indicator
呛翱玖撕失龚于谚稀佰售游吟诌桅炸贡沙捅碴绎斟犁曲且粪头历居律郡馁肠道杆菌和弧菌肠道杆菌和弧菌
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lactose fermentation
Results
colored colonies (red)
non-pathogenic
yes
no
white colonies
pathogenic
Use to differentiate non-pathogenic
from pathogenic
Shigella and Salmonella
--SS agar plate
蛋彦踪佰斩物吮搏舰扯夜浸袜汛梯款娇歉择柱闹脱秘撼吕趁趾腕叙谆徐约肠道杆菌和弧菌肠道杆菌和弧菌
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lactose
Double sugar iron agar slants: contains glucose, lactose, iron acetate 醋酸亚铁 and pH indicator.
Results:
hydrogen sulfide (H2S)
+-
lactose fermentation