Qadri F, Haque M A, Hossain A, Azim T, Alam K, Albert M J
International Center for Diarrheal Disease Research, Bangladesh, Dhaka.
Microb Pathog. 1993 Jun;14(6):441-9. doi: 10.1006/mpat.1993.1043.
Shigella dysenteriae type 1 produce a slime polysaccharide when cultivated in vivo in adult rabbit ileal loops or in vitro in casamino acid yeast extract broth medium which promotes hemagglutination of these bacteria. Seven strains of S. dysenteriae 1 grown in vitro and in vivo and possessing slime polysaccharides resisted killing by normal human serum as compared to bacteria grown under conditions which do not stimulate the production of capsular polysaccharide and did not resist serum killing (mean survival 72% for in vitro growth and 73% for in vivo growth conditions favoring capsule production vs < 2% for growth conditions which do not favor capsule production; P < 0.001 for both comparisons). Similar differences were observed when killing was assessed by phagocytosis (62-78% vs < 2%; P < 0.001). We conclude that capsular polysaccharide may be an additional virulence factor of S. dysenteriae 1.
1型痢疾志贺菌在成年兔回肠袢体内培养或在酪蛋白氨基酸酵母提取物肉汤培养基中体外培养时会产生一种促进这些细菌血凝的黏液多糖。与在不刺激荚膜多糖产生的条件下生长的细菌相比，在体外和体内生长且具有黏液多糖的7株1型痢疾志贺菌能抵抗正常人血清的杀伤作用（有利于荚膜产生的体外生长条件下平均存活率为72%，体内生长条件下为73%，而不利于荚膜产生的生长条件下存活率<2%；两种比较的P均<0.001）。当通过吞噬作用评估杀伤情况时也观察到了类似差异（62 - 78%对<2%；P<0.001）。我们得出结论，荚膜多糖可能是1型痢疾志贺菌的另一种毒力因子。
