[Value of waste water in agriculture. Evaluation of soil bacterial contamination, water table and plant culture]. / Valorisation des eaux usées en agriculture. Evaluation de la contamination bactériologique du sol, de la nappe et de la culture.

The present study aim was to valorize the treated waste water as source of fertilizers for vegetables seed production and to assess the eventual bacteriological contamination risks of soil, plant and phreatic ground water table. The bacteriological analysis of drained water did not reveal any fecal coliforms vertical migration in depth and a low fecal contamination (thermotolerant coliforms) is limited to the levels of superficial horizons. The seed produced by using waste water showed a slightly fecal contamination which disappeared following treatment with a (5% chloride solution. The treated waste water improve the onion seeds production per hectare in spite of the increases of the phytopathogenic hazards.

Rahnella aquatilis, a potential contaminant in lager beer breweries.

The species Rahnella aquatilis has been isolated mostly from water, soil, and, in a few cases, from human clinical specimens; little is known about its ecological role. The application of polyacrylamide gel electrophoresis of soluble proteins, DNA-DNA hybridizations and API 20 E systems has shown that Rahnella aquatilis might also be encountered as a contaminant in lager beer breweries.

[Molecular markers and identification of Campylobacter pylori strains]. / Marqueurs moléculaires et identification des souches de Campylobacter pylori.

Campylobacter pylori was studied to define the classification of species and the typing of strains. The mol p. 100 G + C of 17 strains ranged from 34.1 to 37.5 (average value: 35.2; SD: 1.0). The strains are closely related (80 to 100 p. 100 DNA/DNA relatedness) and to the type strain NCTC 11367. The endonuclease restriction profiles were specific of strains. DNA analysis (REA) is a sensitive method in pathogenic and epidemiological studies.

GC content of DNA of Campylobacter pylori and other species belonging or related to the genus Campylobacter.

DNA of type strain Campylobacter pylori NCTC 11637 and 32 other strains of C. pylori recovered from gastric biopsy specimens was examined by thermal denaturation for its guanine-plus-cytosine (GC) content. The GC content of strain NCTC 11637 was 35.6 mol % (standard deviation (SD) 0.3), and the GC content of the 32 other C. pylori strains ranged from 34.1 to 37.5 mol % (average value 35.2, SD 1.0). A total of 14 type strains of other Campylobacter and Wolinella species were included in this study and the results obtained were compared with those cited in the literature.

A rapid chemical procedure for isolation and purification of chromosomal DNA from gram-negative bacilli.

A rapid and simple method for preparing chromosomal DNA from gram-negative bacilli is presented. It is based on the alkaline (NaOH 0.03 M) lysis of cell walls. The resulting emulsion is purified by proteinase K (0.625 mg/g of wet wt), SDS, and the deproteinizing agent (chloroform isoamyl alcohol). The purity, molecular nature, and yield of DNA obtained by the present method are compared with those of DNA extracted by Marmur's procedure and a Marmur's modified procedure. We have developed and standardized this original method to isolate double-stranded DNA, free of proteins and RNA contamination and with a significantly higher yield of DNA than the two other methods. This procedure is particularly useful for strains with low growth and can be applied in every field concerned with DNA analysis.

Separation of Escherichia adecarboxylata from the "Erwinia herbicola-Enterobacter agglomerans" complex and from the other Enterobacteriaceae by nucleic acid and protein electrophoretic techniques.

The species Escherichia adecarboxylata was examined for DNA relatedness to the "Erwinia herbicola-Enterobacter agglomerans" complex and to other members of the family Enterobacteriaceae. DNA-DNA hybridizations (nitrocellulose filter method) showed that strains received as E. adecarboxylata were highly related to each other (73-100% homology). Three strains of E. agglomerans and one strain of E. herbicola showed, respectively, 77, 96, 97 and 92% relatedness with the labelled DNA of E. adecarboxylata. Two groups (E2 and E3) of "atypical coliforms" previously described by Gavini et al. (1983) showed high reassociation values (76-79% and 80-89%, respectively) with E. adecarboxylata. Most of these strains produced similar or nearly identical protein electrophoregrams. All these strains were therefore classified in E. adecarboxylata. This taxon yielded hybridization values lower than 53% with the previously described phenetic or genetic groups belonging to or related to the "herbicola-agglomerans" complex and values lower than 64% with 56 other species of the Enterobacteriaceae. It was concluded that E. adecarboxylata is a species different from E. agglomerans and the other species of the family Enterobacteriaceae. A new definition of the species E. adecarboxylata is presented.