嗜麦芽假单胞菌酪氨酸酶基因在类产碱假单胞菌中的转移与表达

类产碱假单胞菌 (Pseudomonaspseudoalcaligenes)是从盐城市农村粪池中采集的自然病死蝇蛆体内分离的具有显著杀蛆作用的细菌 ,野外使用易受阳光中紫外线的影响而失活。黑色素具有很强的抗辐射作用。将构建的含有嗜麦芽假单胞菌酪氨酸酶基因的质粒pWSY导入类产碱假单胞菌体内 ,使后者获得了稳定产生黑色素的能力。Southern杂交实验证实酪氨酸酶基因来源于嗜麦芽假单胞菌。SDS PAGE电泳显示该重组子体内额外表达了一分子量约为 1 8kD的蛋白 ,该蛋白很可能就是重组子表达的酪氨酸酶。经测定 ,重组子抗辐射作用明显增强 ,有效杀蛆时间显著延长 ,对畜、禽安全     

假单胞菌属的一个新种

从桔汁矿化水饮料中分离到一株编号为9191的革兰氏阴性短杆菌,其形态、生理生化特性与假单胞菌属已报道的种均不相同.该菌株具极生单鞭毛,氧化酶和触酶均阳性;O-F葡萄糖为非发酵型,不产生荧光色素,不产生脓菌素,不产生类胡萝卜色素,对葡萄糖呈碱反应.经类脂粒染色后细胞内可见PHB颗粒积聚.脲酶阳性,硝酸盐还原阳性,反硝化阴性;不水解淀粉和明胶,精氨酸双水解酶阴性;41℃下不生长,在麦康凯和SS平板上不生长.在0.85%CaCl_2的牛肉汤中不生长;利用β-羟基丁酸作为唯一碳源;DNA中G+C含量为65.15mol%.因此定为假单胞菌属中的一个新种.根据其对生理盐水敏感的特性,命名为盐敏假单胞菌(Pseudomonas halosensibilis Zou ＆ Cai nov.sp.).     

PSEUDOMONAS AERUGINOSA IN DRINKING WATER

SUMMARY: The literature concerning antagonism between Pseudomonas aeruginosa and Escherichia coli , the natural habitat of the former and its potential pathogenicity, has been briefly surveyed. Experimental work showed that the two organisms can coexist in pure water, but in mixed cultures in peptone water Ps. aeruginosa can inhibit E. coli , though not in the early stages of growth and only within a critical range of peptone concentration. Ps. aeruginosa might therefore reduce the coli-aerogenes content in grossly polluted water but would not normally interfere with the determination of the actual coli-aerogenes content at the time of sampling. Water supplies containing many Ps. aeruginosa but few or no coli-aerogenes bacteria were found to be relatively common in Northern Israel and in view of the faecal origin of the former, and its potential pathogenicity, it is concluded that this organism should be taken into account, as well as coli-aerogenes bacteria, in assessing the suitability of water for drinking purposes.     

假单胞菌属引起医院感染332例临床分析

目的 了解假单胞菌医院感染状况及对抗菌药物的敏感率。方法 调查１９９４年７月～１９９８年６月４年间发生的假单胞菌医院感染３３２例,分析原发病、诱发因素、临床特点、血白细胞、疾原菌分布及Ｋ－Ｂ法药敏情况。结果 血液系统疾病、慢性阻塞性肺气肿和外伤患者易引起假单胞菌医院感染,常见感染部位为呼吸道、泌尿道。结论 机体免疫功能受损者易患假单胞菌医院感染,病原菌对环丙沙星、阿米卡星、头胞他啶、多粘菌素Ｂ的敏感性较好。     

PSEUDOMONAS AERUGINOSA INFECTIONS OF THE EYE

Pseudomonas aeruginosa seldom invades the body except in persons or in organs lacking natural defenses, and usually the infection is chronic rather than acute, evoking little systemic response. When introduced into the cornea, however, as in penetration by a foreign body or in contaminated medicines, it acts with extreme virulence, in many cases causing blindness and even necessitating enucleation.Although many attempts at control of Ps. aeruginosa, even with powerful antibiotics, have been unsuccessful, polymyxin B appeared to have good effect and was tested in experimental infection of the cornea in rabbits.It was demonstrated by preliminary studies in vitro that polymyxin B was effective against nine strains of Ps. aeruginosa which on inoculation caused rapidly progressive ulcers in the corneas of rabbits.A strain of proved virulence was introduced into both eyes of each of 18 rabbits. The left eyes only were treated with subconjunctival injections at 48-hour intervals of a solution of polymyxin B, to which epinephrine was added as a vasoconstrictor to prevent rapid dispersion. The right eyes remained untreated as controls.In five of the six rabbits treated immediately after inoculation, the treated eyes remained clear, while moderate infiltration developed in the sixth. In the six rabbits not treated for 24 hours after inoculation, ulcers developed but remained localized during therapy. In those not treated for 48 hours after inoculation, ulcers developed before treatment began but did not spread as rapidly as in the controls.Hyaluronidase was added to the preparation for half the rabbits in each group but had no perceptible beneficial effect.     

荧光假单胞菌抗噬菌体菌株的选育

本实验从荧光假单胞菌（Ｐｓｅｕｄｏｍｏｎａｓｆｌｕｏｒｅｓｃｅｎｓ）ＡＳ—３菌株的不正常发酵液中分离到一种噬菌体,将其命名为ＰＦＡＳ。ＡＳ—３菌株能利用葡萄糖发酵产生Ｄ－异维生素Ｃ的前体物质２－酮基－Ｄ－葡萄糖酸。电镜观察表明ＰＦＡＳ噬菌体呈蝌蚪形,具有直径为６６ｎｍ的六角形头部及长１１７ｎｍ的尾部。通过紫外线诱变及自然选育两种途径,配合简便有效的初筛方法,经多次分离、纯化、复筛最终在摇并发酵试验中获得６株产量稳定地高于对照敏感菌的抗噬菌体菌株,可望用于生产。     

泡囊假单胞菌的分离及鉴定

从一例心包积液患者的心包液中,分离到一株氧化代谢、氧化酶阳性,具单极毛运动的革兰氏阴性杆菌。经形态、生理生化特性鉴定,DNA的G+C mol％测定和Biolog自动系列的验证,确认为泡囊假单胞菌(Pseudomonas vesieularis)。指出该菌可使免疫力低下患者发生感染。对该菌分类地位的变迁进行了讨论。