Detecting clinical activity in systemic lupus erythematosus with an archaeal poly(ADP-ribose) polymerase-like thermozyme: a pivotal study.

The clinical usefulness of an immunotest was evaluated by using purified poly(adenosine diphosphate (ADP)-ribose) polymerase from Sulfolobus solfataricus (PARPSso) as an antigen to detect the presence of abnormal anti-PARP antibodies in the sera of patients with systemic lupus erythematosus (SLE) at different clinical stages. Sera from 44 patients with SLE, subgrouped on the basis of disease activity (16 with inactive disease, 28 with active disease) were analysed with a new immunotest to detect anti-PARP antibodies, and with an immunofluorescent (IIF) assay for antinuclear antibodies (ANA) detection. ANA detection by IIF revealed that sera of healthy subjects were negative, whereas sera from patients with SLE were positive in all cases (13 positive at 1:80, 15 at 1:160, 15 at 1:320, 1 at 1:640, v/v). Anti-PARP activity was higher in ANA-positive patients than in controls (p = 0.005). Within the group of SLE sera, disease and anti-PARP activity was increased more significantly in patients with active than in those with inactive disease (p < 0.001 and p = 0.001, respectively). Correlation between anti-PARP and disease activity in SLE patients was statistically significant (p < 0.001). PARPSso seems to be suitable for detecting anti-PARP antibodies and could play a role as a serological marker of disease activity in patients with SLE.

The (ADP-ribosyl)ation reaction in thermophilic bacteria.

Species of Alicyclobacillus, Bacillus and Thermus genera were selected in order to study the possible presence of the (ADP-ribosyl)ation system. These bacteria are thermophilic, aerobic, and were isolated from different geothermal sources. Both activity and expression of (ADP-ribosyl)ating proteins were tested in cells at different growth phases, and evidence of an active system was obtained in all analyzed microorganisms, with comparable enzymatic levels. Immunochemical analyses with polyclonal antibodies against both eukaryotic anti-(ADP-ribose) transferase and anti-poly(ADP-ribose) polymerase revealed, for all tested organisms, an immunosignal localized in the range of molecular masses between 43-53 kD. Several proteins of various molecular masses were found as ADP-ribose acceptors. Reaction product analyses showed mono(ADP-ribose) to be the only synthesized compound.

Yeast (ADPribosyl)ation: revisiting a controversial question.

The controversy about the occurrence of an (ADPribosyl)ating activity in yeast is still standing up. Here we discuss this topic on the basis of results obtained with classic experiments proposed over years as basis to characterize an (ADPribosyl)ation system in any organism. Independent results obtained in two different laboratories were in line with each other and went towards the occurrence of an active (ADPribosyl)ating system in Saccharomyces cerevisiae. In fact data collected from nuclear preparations of cultured cells matched those from baker's yeast and lyophilized yeast cells. Yeast (ADPribosyl)ating enzyme is a protein of 80-90 kDa, as determined by electrophoresis on polyacrylamide gel in sodium dodecyl sulphate, followed by immunoblotting with antibodies against anti-poly(ADPribose) polymerase catalytic site. It synthesizes products, that, after digestion with phosphodiesterase, co-migrates mainly with phosphoribosyl adenosine monophosphate after thin layer chromatography on silica gel plate.