Toxicity of density separation media to Escherichia coli and Mycobacterium strain PC01: implications for density-separation of soils and sediments.
نویسندگان
چکیده
Separation of low-density sediment detritus in CsCl solution is a promising technique for benthic studies. The known toxicity of CsCl suggests the possibility of toxicity in the separated sediment. Fluoranthene biodegradation by Mycobacterium strain PC01 was used to probe microbial activity in sediment following density separation. Complete inhibition of biodegradation occurred in sediment previously contacted with CsCl media, but washing eliminated inhibition. Washing may not be preferable for subsequent study of the separated sediment, suggesting the need for less toxic media. We studied how various density separation media affected the viability of Escherichia coli to quantify toxicity. Although all media decreased viability, Nycodenz(R) and metrizamide were one to three orders of magnitude less toxic to bacteria than CsCl or Na2WO4. Toxicity was generally related to ionic strength. These results demonstrate that iodinated benzoic acids are superior to metal salts solutions for preserving biological activity on separated sediment or soil.
منابع مشابه
media and specific growth rate selection for high-cell-density cultivation of recombinant escherichia coli producing hGM-CSF in fed-batch process
متن کامل
Preliminary Beneficiation and Washability Studies on Ghouzlou's Low-Ash Coal Sample
In the present research work, a low-ash coal, from Ghouzlou deposit in Iran, with an average ash content of 12% was subjected to some beneficiation experiments such as heavy media separation and flotation. Sieve analysis showed that 62.3% of the coal sample with the size of +2 mm had around 7.3% ash contents. Also, heavy media tests carried out on five size fractions revealed that by setting th...
متن کاملEffects of ackA, pta and poxB inhibition by antisense RNA on acetate excretion and recombinant beta interferon expression in Escherichia coli
Introduction: Escherichia coli (E.coli) is one of the most widely used hosts for the production of recombinant proteins. The main problem in getting high product yields and productivity is the accumulation of acetic acid (acetate) as an unwanted metabolic by-product. In this study, an antisense-based strategy as a metabolic engineering approach was employed to hamper the acetate excretion probl...
متن کاملOptimization of secretory expression of recombinant hGM-CSF in high cell density cultivation of recombinant Escherichia coli using Taguchi statistical method
Human granulocyte macrophage colony stimulating factor (hGM-CSF) has many therapeutic applications.In this study, in order to verify the purification process, the effect of carbon source, IPTG concentration andpost-induction time on the secretion of recombinant hGM-CSF into the culture medium by recombinantEscherichia coli during high cell density cultivation were evaluated by...
متن کاملScreening of antibacterial producing actinomycetes from sediments of the Caspian Sea
Actinomycetes are interesting as a main producer of secondary metabolites and industrial antibiotics from marine environments. A total of 44 strains of actinomycetes were isolated from Caspian Sea sediments at a depth of 5-10 m. Preliminary screening was done using cross-streak method against 2 gram-positive and 4 gram-negative pathogen bacteria. The most potent strains MN2, MN3, MN38, MN39, MN...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- FEMS microbiology ecology
دوره 43 2 شماره
صفحات -
تاریخ انتشار 2003