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Biomedical subjects

A E Goodman

Publications and source records attributed to A E Goodman.

26 records · Page 2Linked to original sources
PubMed1990

Behavior of the hybrid plasmid pNSW301 in Zymomonas mobilis grown in continuous culture.

The stability of the plasmid pNSW301 which was formed by cointegration of the Inc W R plasmid Sa and the 14.5-kb pNSW1 plasmid of Zymomonas mobilis ZM6100 was investigated in ZM6100(pNSW301) grown in continuous culture without antibiotic selection. The cointegrate plasmid, pNSW301, was found to be structurally unstable and a total reduction in the size of pNSW301 of approximately 21 kb occurred during growth in continuous culture. Following a systematic study, a number of deletion derivatives of pNSW301 were isolated and used to transform Escherichia coli HB101, with the exception of pNSW312. The plasmid pNSW312 was 100% stable in ZM6100(pNSW312) in continuous culture but was unable to replicate in E. coli.

DNA Probes↗
PubMed1989

Pre- and postjunctional actions of neuropeptide Y and related peptides.

The effects of neuropeptide Y (NPY) and related peptide fragments on blood pressure and vagal action at the heart were compared in the anaesthetized rat. A change in vagal action was taken as a measure of presynaptic activity and a change in blood pressure was taken as a measure of postsynaptic activity. NPY, NPY-(13-36), PYY-(13-36), des-Ser22-NPY-(13-36) and a stabilized 13-36 analogue of NPY (ANA NPY) all exerted pressor actions and attenuated vagal action at the heart. The maximum vagal inhibitory or presynaptic action in order of potency was NPY, ANA-NPY, PYY-(13-36) significantly greater than NPY-(13-36), des-Ser22-NPY-(13-36). The order of potency for the half time of this effect was NPY, ANA-NPY significantly longer than PYY-(13-36) and NPY-(13-36), which were significantly longer than des Ser22-NPY-(13-36). For the pressor or postsynaptic effects, NPY increased blood pressure significantly more and for a longer duration than all the 13-36 fragments, which were not demonstrably different in this respect. These results are consistent with the proposal that there are two populations of NPY receptors. The C-terminal flanking peptide of NPY (CPON) and desamido-NPY had no effect on either vagal action at the heart or on blood pressure.

Animals↗
PubMed1987

Behavior of the IncW plasmid Sa in Zymomonas mobilis.

The stability of the broad-host-range IncW R plasmid Sa in Zymomonas mobilis ZM6100(Sa) was monitored using three antibiotic resistance markers carried by Sa. When grown in batch culture without selection, ZM6100(Sa) rapidly lost the Sa plasmid. When grown with selection for either kanamycin or spectinomycin resistance, the three Sa markers were retained in at least 90% of the population, with spontaneous loss of chloramphenicol resistance being observed in the rest of the population. When ZM6100(Sa) was grown with selection for chloramphenicol resistance, the Sa plasmid either formed a cointegrate plasmid, designated pNSW301, with a native ZM6100 plasmid or was lost except for the chloramphenicol resistance marker. Possible transportation of the chloramphenicol resistance region of Sa to the Z. mobilis chromosome was indicated by hybridization data. The cointegrate plasmid, pNSW301, was maintained stably, except for spontaneous loss of chloramphenicol resistance, in Z. mobilis without selection for 300 generations. pNSW301 was able to replicate in Escherichia coli and was capable of conjugal transfer.

Chloramphenicol Resistance↗
PubMed1984

Transformation of Zymomonas mobilis by a hybrid plasmid.

The transformation of Zymomonas mobilis by plasmid DNA was achieved using a modification of the CaCl2 method for Escherichia coli. The highest frequency of transformation obtained was 5 X 10(3) transformants/micrograms DNA. The success of the method depended upon the use of a plasmid which is a cointegrate between a Z. mobilis cryptic plasmid and an E. coli plasmid carrying two selectable drug resistance markers.

Cloning, Molecular↗
PubMed1984

Zymomonas ethanol fermentations.

Studies on various industrial raw materials indicate that a zymomonas process has its greatest commercial potential in fermenting starch-based substrates. High yields, productivities and ethanol concentrations can be achieved. Genetic manipulation is now being used to extend the substrate range to lactose and other carbohydrates.

Biotechnology↗
PubMed1983

High-productivity alcohol fermentations using Zymomonas mobilis.

A process is under development at the University of New South Wales to produce fermentation ethanol faster and more efficiently. The process is based on the micro-organism Zymomonas mobilis, which has higher specific rates of ethanol production and higher yields when compared with the traditionally used yeasts. By using hollow fibre membranes for cell recycle, high productivity continuous processes have been studied at laboratory-scale. Pilot scale evaluations (500 litres) are now in progress through Licence Agreements between the University and industry. Genetic manipulation and recombinant DNA techniques are being used to increase the ethanol tolerance and broaden the substrate range. Most recently glucoamylase genes from Aspergillus niger have been cloned into Escherichia coli K12 as part of a programme to enable direct fermentation of starch to ethanol by Z. mobilis.

Bacteria↗
PubMedDate not supplied

A strategy for obtaining active mammalian enzyme from a fusion protein expressed in bacteria using phospholipase A2 as a model.

An active preparation of human phospholipase A2 (PLA2) was made after expression as an insoluble fusion protein in Escherichia coli. The new key elements required for PLA2 isolation were the maintenance of the fusion protein in solution after the initial solubilization and the use of a tryptophan cleavage procedure for regeneration of native PLA2 from the fusion protein. The fusion protein was composed of a beta-galactosidase leader peptide incorporating six consecutive threonine residues to aid in insoluble inclusion body formation, followed by a tryptophan adjacent to the N-terminus of PLA2. The fusion protein was purified from cell lysates, and the leader peptide was cleaved on the C-terminal side of the tryptophan residue with N-chlorosuccinimide. The released PLA2 was refolded and renatured to produce an enzyme with activity comparable to that of other phospholipases A2.

Amino Acid Sequence↗