Conditions Affecting Germination of Clostridium botulinum 62A Spores in a Chemically Defined Medium

Author:

Rowley Durwood B.1,Feeherry Florence1

Affiliation:

1. Microbiology Division, Food Laboratory, U.S. Army Natick Laboratories, Natick, Massachusetts 01760

Abstract

Spores of Clostridium botulinum type 62A were germinated in a chemically defined medium (8 m m l -cysteine, 11.9 m m sodium bicarbonate, 4.4 m m sodium thioglycolate; buffered with 100 m m TES, p H 7.0). The rate and extent of germination were increased when an aqueous spore suspension was heated sublethally (80 C, 60 min) before addition to the germination medium. Neither sublethal nor lethal doses of gamma radiation had any marked effect on subsequent germination. Maximum germination (>90% in 2 hr) in the defined medium occurred in the p H range of 6.5 to 7.5, at 30 to 37 C, with an l -cysteine level of 8 m m . Increasing l -cysteine to 32 m m increased the rate (over that with 8 m m l -cysteine) but not the extent of germination. The rate and extent of germination increased with NaHCO 3 addition to 8.3 m m , but increasing levels to 11.9 m m had no further effect. For maximum germination, 2.2 m m sodium thioglycolate was required and higher levels (to 8.8 m m ) had no further enhancing or inhibitory effect. Under optimal conditions for germination, 97% of the spores had become heat sensitive; 98% had become sensitive to radiation; 88 and 91% had become phase dark and stainable, respectively, and the spore suspension had lost 46% of its initial optical density by 2 hr. Loss of heat resistance preceded loss of radiation resistance, acquisition of stainability, and phase darkening by about 12 min.

Publisher

American Society for Microbiology

Subject

Molecular Biology,Microbiology

Reference23 articles.

1. Radiation sterilization of prototype military foods. II. Cured ham;Anellis A.;Appl. Microbiol.,1967

2. Spore germination in Clostridfum tyrobutyricum. I. Action of various compounds on the initial stage;Berg J. L.;Ann. Inst. Pasteur,1969

3. Adaptation of biphasic culture technique to the sporulation of Clostrfdlum botulinum type E;Bruch M. K.;J. Food Sci.,1967

4. Fermentative activities of control and radiation-"killed;Costilow R. N.;J. Bacteriol.,1962

5. Heat activation inducing germination in the spores of thermotolerant and therrophilic aerobic bacteria;Curran H. R.;J. Bacteriol.,1945

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3