Jewel Parker

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During asparagine starvation the frequency of lysine for asparagine substitutions increases to levels that enable one to isolate and sequence mistranslated protein. We have used site-directed mutagenesis to construct a series of derivatives of the gene encoding the coat protein of the bacteriophage MS2. The mutant set constructed has either AAU or AAC as(More)
A 6-kb fragment of DNA, which complemented defects in the alcohol dehydrogenase (ADH)-encoding gene (adhE) of Escherichia coli, was cloned into a multicopy vector. Both ADH and coenzyme-A-linked acetaldehyde dehydrogenase (ACDH) activities were encoded by the plasmid, pHIL8. The adhE gene was identified as an open reading frame of 891 codons encoding an Mr(More)
A potential physiologic role of extracellular adenosine triphosphate (ATP) on platelet function is proposed in this report. It is widely accepted that ATP competitively inhibits adenosine diphosphate (ADP)-induced platelet aggregation. Our observations of platelet aggregation with the agonists, collagen, epinephrine, and ADP in the presence of 180 mumol/L(More)
The coat protein of the small RNA virus MS2 shows charge heterogeneity in vivo. In most strains there is a basic satellite of the native protein. We have shown that this basic satellite is greatly diminished or absent in strains with the streptomycin-resistant allele, rpsL, a mutation which leads to increased translational accuracy. Further, the satellite(More)
In all vertebrate embryos, segmental streams of cranial neural crest cells migrate to form the pharyngeal arches and differentiate into cartilages and bones of the head skeleton. In gnathostomes, the head skeleton has a dorsoventral (DV) polarity from its first appearance: dorsal and ventral cartilages of different shapes (such as the upper jaw and lower(More)
A grapelike odor is often of diagnostic importance in detecting the growth of Pseudomonas aeruginosa in culture and in burn wounds. The compound responsible for the odor has been identified as 2-aminoacetophenone by mass spectroscopy. Although the grape odor is sometimes difficult to detect in culture media, gas chromatographic, fluorometric, and(More)
Phagocytosis of Opa+ Neisseria gonorrhoeae (gonococcus, GC) by neutrophils is in part dependent on the interaction of Opa proteins with CGM1a (CEACAM3/CD66d) antigens, a neutrophil-specific receptor. However, the signaling pathways leading to phagocytosis have not been characterized. Here we show that interaction of OpaI bacteria with neutrophils or(More)
Amino acid starvation of a variety of different types of cells has been reported to induce protein degradation and also specific mistranslation. For certain amino acid starvations, the mistranslated protein, which contains specific amino acid substitutions, can be separated and quantified by two-dimensional polyacrylamide gel electrophoresis. In this paper,(More)
This report demonstrates that platelets possess P2 purinoceptors with unique properties that distinguish them from the ADP (P2T) receptor. Extracellular ATP, and its poorly hydrolyzable analogues, inhibit collagen- and U46619 (a thromboxane mimetic)-induced platelet aggregations. Adenosine deaminase was without effect on ATP action while reversing the(More)
The bioluminescent detection of ATP released from activated platelets is an important diagnostic and experimental assay. Potential errors in the interpretation of the data may be introduced due to the lability of luciferin-luciferase and the amount of platelet agonist employed. Loss of luciferin-luciferase activity is temperature dependent with a 50%(More)