The nutritional requirements and culture conditions affecting biosynthesis of L-asparaginase in a mutant ofEscherichia coli HAP designated strain A-1 were studied. Asparaginase activity was increased by the addition of L-glutamic acid, L-glutamine, or commercial-grade monosodium glutamate. The rate of enzyme synthesis was dependent on the interaction between the pH of the culture and the amount of oxygen dissolved in the medium. A critical oxygen transfer rate essential for asparaginase formation was identified, and a fermentation procedure is described in which enzyme synthesis is controlled by aeration rate. Enhancement of L-asparaginase activity by monosodium glutamate was inhibited by the presence of glucose, culture pH, chloramphenicol, and oxygen dissolved in the fermentation medium.
Congress enacted the Consumer Review Fairness Act which was intended to largely prohibit the use of clauses preventing such reviews. However, the concern of companies regarding the "troll-like" virulent reviews, often posted solely for vengeance purposes, remains valid. This Article posits that the Consumer Review Fairness Act still allows contract clauses which prohibit reviews that are defamatory, and also reviews that are "abusive." Abusive reviews which should still be contractually prohibitable include the virulent, excessively negative "troll-like" reviews. (One important caveat-to date, California, Maryland, and Illinois have enacted their own state laws banning non-disparagement clauses, which do not presently contain the "abusive" exception as does the CRFA, and thus merchants subject to these laws cannot ban any consumer reviews of any type-troll or otherwise). Moreover, this Article further argues that the implied duty of good faith and fair dealing can be argued to prohibit such abusive reviews, regardless of the presence of an express clause banning reviews.
A mating between Escherichia coli 4318 (thi leu Las-Hfr) and E. coli A-1 (Met-Las' F-) resulted in the formation of prototrophic recombinants having L-asparaginase activities at three distinct levels. The physiology of L-asparaginase synthesis in these recombinants is described. One class of recombinants produced significantly more L-asparaginase than E. coli A-1. L-Asparaginase synthesis in the recombinants was inhibited by the presence of dissolved oxygen in the medium and was transiently repressed by the presence of glucose in the same manner as that observed in the parental strains. L-Asparaginase activity was increased by the addition of oxalacetate as well as other members of the tricarboxylic acid cycle.
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