Relationships Between Initial Nutrient Concentration and Total Growth

Abstract

The relationship observed between maximal attainable growth in a microbial population and initial concentration of limiting nutrient depends upon the parameter selected for measurement of growth. A linear relationship is found only when cell mass is the parameter. When population is used as the measure of growth, the relationship is: Nmax = KtCo8, where Nmax is the maximal attainable population, Co is the initial concentration of limiting nutrient and K' and s are constants. The use of this expression in demonstrating subtle differences between strains is shown. I This paper is based on a dissertation submitted by the senior author to the faculty of Iowa State University in partial fulfillment of the requirements for the Ph.D. degree.

A new chemically-defined medium for Bacillus subtilis (168) NCIMB 12900

“…Bucillussubtilis 168 was used in studies for the production and quantification of polyphosphorylated purines during nutrient limitation. The polyphosphorylated purines, guanosine-3'diphosphate-5'-diphosphate (Magic Spot I) and guanosine-3'-diphosphate-Sf-triphosphate (Magic Spot 11) are produced by B. subtilis in response to nutrient limitation and are involved in the commitment to endosporulation (Ecker et al 1961;Klemperer et al 1979;Matin et ul. 1989;Brown et ul.…”

Growth characteristics of mutant strains of Escherichia coli

“…Total counts were made using a membrane filter technique (Ecker and. Lockhart, 1959 a Ecker and Lockhart (1961c). To a sample containing 10?…”

“…It was reported by Ecker and Lockhart (1961c) that, under conditions of a single limiting nutrient, the relation ship between total attainable population in a culture and concentration of limiting nutrient can be expressed as:…”

“…The value of logg C 0 at which G max is most nearly the same for the,diverse strains is about 9*5» Therefore the nitrogen-limited cultures were limited at C Q -800 p.g The latter variation may be accounted for by the uses to which glucose and nitrogen are put during growth. It has been suggested (Scker and Lockhart, 1961c) that glucose 1.7…”

Influence of temperature on macromolecular composition of Escherichia coli

“…This rate will support the growth of E_. coli up to a population of 10^^ cells/ml of medium (Ecker and Lockhart, 1961).…”