Isoprenoid quinone composition of representatives of the genus Campylobacter

The isoprenoid quinone composition of 17 strains representing nine species or sub-species of the genus Campylobacter was investigated. All strains produced similar respiratory quinone patterns consisting of unsaturated menaquinones with six isoprene units and a novel unidentified quinone. Mass spectral analysis indicate the unknown compound has six isoprene units and a formula C₄₂H₅₈O₂. The present study indicates respiratory quinones may be useful generic markers for Campylobacter.     

Biotype and macromolecular profiles of cytotoxin-producing strains of Helicobacter pylori from antral gastric mucosa

Biotype, genome, protein and plasmid profile diversity amongst 40 epidemiologically unrelated strains of Helicobacter pylori was studied. Strains were API Zym biotypes II, III and IV but most (87%) were biotype II. Four subsets of strains were defined on a combination of motility (56% positive) and cytotoxin production (44% positive). A close association (P = 0.45) between these two features was observed for 69% of strains. Each strain of H. pylori had a unique DNA type defined by either HaeIII or HindIII total digest patterns and by ribopatterns, except for DNA of the rare strains not cut by these endonucleases. Strain diversity was confirmed by one-dimensional SDS-PAGE electrophoretic protein patterns. No consistent associations between cytotoxin activity and overall ribopattern or band subsets within a ribopattern were detected. Some strains (39%) contained a plasmid but the presence of plasmids was not consistently associated with either cytotoxin activity, biotype, motility or ribopattern. We conclude that the cytotoxin-producing strains of H. pylori were genomically as diverse as the non-cytotoxin producing strains.     

The problems and prospects of integrated control of Agonoscena pistaciae Burck. and Laut. (Hom., Sternorrhyncha) in Greece

Abstract: A study of the role of natural enemies of Agonoscena pistaciae Burck. and Laut. populations, in a pistachio orchard located in the Makrakomi area of Central Greece, was carried out during 1999–2000. Agonoscena pistaciae is economically the most important psyllid species of pistachio in Greece and causes considerable damage. Its adult population evaluation is clearly distinguishable in two phases. The first phase, from early April until the end of July, is characterized by slow population development. In the second phase, from the end of July until the fall of the leaves, the population density of this insect increases rapidly and reaches high levels. During this second phase, the presence of the predator insects Chrysoperla carnea Steph., Anthocoris nemoralis F and of the parasitoid Psyllaephagus pistaciae Ferriere is noteworthy. Among these, the most important is the parasitoid, which appears in satisfactory numbers between the end of July and the end of September/beginning of October and plays a significant role in reducing the populations of A. pistaciae that are on the point of hibernating.