Disorders of candidacidal activity and other neutrophil functions in three cases of chronic candidiasis.

Three unrelated cases of recurrent and untreatable candidiasis have been followed for about one year. A persistent in vitro defect of neutrophil candidacidal activity characterized the three cases, while other neutrophil functions were shown to be only transiently impaired during the period of observation. None of the three cases could be identified with previously described granulocytopathies.

A defect in neutrophil motility in two siblings with recurrent infections and a remarkable family history.

Two siblings with recurrent infections were found to have impaired neutrophil motility. The same association of infections (otitis media, bronchitis, chronic diarrhoea) has caused seven fatalities in the paternal side of the family, suggesting genetic implications.

A new familial defect in neutrophil bactericidal activity.

A 4-year-old boy with recurrent infections and his clinically healthy father showed a severe, isolated defect in bactericidal activity of peripheral neutrophil leukocytes (the mother and the only sister were normal). Lymph nodes, spleen and liver of the child presented a massive infiltration by macrophages. Such infiltration and the segmentary albinism of the hair resemble traits of the Chediak-Higashi syndrome, but some of the most relevant traits of this syndrome are absent, since all other neutrophil functions were normal in our patient.

A simplified procedure for the analysis of DNA polymerase III levels in Bacillus subtilis strains.

A simple and reproducible procedure is described which allows the fast and almost quantitative removal of DNA polymerases I and II from DNA polymerase III, in crude extracts of polA+ strains of Bacillus subtilis. The procedure entails streptomycin sulfate and ammonium sulfate fractionations; subsequent analysis of the partially purified preparation by G-200 chromatography, DEAE cellulose chromatography and density gradient sedimentation, shows that the ammonium sulfate fraction contains less than 5% of the total activity as DNA polymerase I and less than 2% as DNA polymerase II. The purification procedure, up to the ammonium sulfate step, was utilized for the analysis of the level of DNA polymerase III in several B.

On the identity of dnaP and dnaF genes of Bacillus subtilis.

The dnaP strains of Bacillus subtilis are altered in the initiation of DNA replication at high temperature (Riva et al., 1975). Fine mapping of the gene shows that it is located very close to the dnaF gene described by Karamata and Gross (1970) and mapped by Love et al.

[Various cases of acute gastroenteritis due to Salmonella Paratyphi C].

Five cases of acute gastroenteritis due to Salmonella Paratyphi C observed in the province of Trieste during 1975 are described. It is deduced from the clinical findings and the history in each case that this infection was imported, and favoured by the geographical location of the city and prior mutilating gastrointestinal surgery. The in vitro and in vivo effect of commonly employed antibiotics on this species is assessed.

Pleiotropic, extragenic suppression of dna mutants in Bacillus subtilis.

Thermosensitive (dna) mutants of Bacillus subtilis defective in deoxyribonucleic acid replication can be divided into two groups on the basis of their ability to spontaneously yield secondary mutants with an HDS phenotype (thermoin-sensitivity and resistance to aryl-azo-pyrimidines) at frequencies higher than 10(-8). Such a phenotype is due to alleles at the hds locus (mapping close to cysA), which act as extragenic pleiotropic suppressors. HDS suppressibility has been used as a screening tool to identify new dna strains among uncharacterized temperature-sensitive mutants.

An intracellular endonuclease of Bacillus subtilis specific for single-stranded DNA.

We have fractionated from extracts of Bacillus subtilis the DNase activity specific for single-stranded DNA; the activity separates in two main fractions on Sephadex G-200, a larger one (Mr greater than 400 000) and a smaller one (Mr approximately 30 000). We have purified the smaller, more abundant fraction nearly 3000-fold. The purified enzyme has a pH optimum close to 8, is activated by Ca2+, and is inhibited by EDTA; the enzyme hydrolyses single-stranded DNA at a rate approximately 40 times greater than double-stranded DNA.

[13 years of Australia antigen. Critical notes].

The main points in the history of Australia antigen in the ten years since its discovery are summarised. Reference is made to an epidemic episode observed in a community in discussing a number of aetiopathogenetic and nosological features recently codified by official infectivology.

Genetic and enzymic studies on the recombination process in Bacillus subtilis.

We have isolated recombination deficient mutants of Bacillus subtilis on the basis of their sensitivity to methyl-methane-sulfonate or ultraviolet light, or of their inability to be transformed on solid medium. We have analyzed the mutants for several recombination and repair properties; we have grouped them in 5 classes on the basis of their phenotype and tested them for the activity of several enzymes acting on DNA, ie. DNA polymerase, polynucleotide ligase, ATP dependent DNase, and a DNase acting on single-stranded DNA.

Properties of a Bacillus subtilis strain lacking DNA polymerase I.

We have isolated a mutant of Bacillussubtilis deficient in DNA polymerase I, denominated polA42, which shows a reduced ability to repair the damage to DNA by UV radiation, MMS and mitomycin C;the ability to perform recombination is not appreciably impaired.DEAE cellulose chromatography allows the separation of polymerases I and II from the parental strain;a simple procedure is also described which allows to separate rapidly the polymerases II and III of the mutant strain. The three separated polymerases have similar catalytic properties but they can be distinguished for their sensitivity to inhibitors: PCMB inhibits polymerases II and III but not polymerase I; HPUra inhibits only polymerase III.