The aim and novelty of this paper are found in assessing the influence of inhibitors and antibiotics on intact cell MALDI-TOF mass spectra of the cyanobacterium Synechococcus sp. UPOC S4 and to check the impact on reliability of identification. Defining the limits of this method is important for its use in biology and applied science. The compounds included inhibitors of respiration, glycolysis, citrate cycle, and proteosynthesis. They were used at 1-10 μM concentrations and different periods of up to 3 weeks. Cells were also grown without inhibitors in a microgravity because of expected strong effects. Mass spectra were evaluated using controls and interpreted in terms of differential peaks and their assignment to protein sequences by mass. Antibiotics, azide, and bromopyruvate had the greatest impact. The spectral patterns were markedly altered after a prolonged incubation at higher concentrations, which precluded identification in the database of reference spectra. The incubation in microgravity showed a similar effect. These differences were evident in dendrograms constructed from the spectral data. Enzyme inhibitors affected the spectra to a smaller extent. This study shows that only a long-term presence of antibiotics and strong metabolic inhibitors in the medium at 10-5 M concentrations hinders the correct identification of cyanobacteria by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF).

• Klíčová slova
• MALDI, Synechococcus, antibiotic, cyanobacterium, inhibitor, metabolism,
• MeSH
• antibakteriální látky toxicita   MeSH
• antimycin A analogy a deriváty   toxicita   MeSH
• azidy toxicita   MeSH
• buněčné dýchání účinky léků   MeSH
• chloramfenikol toxicita   MeSH
• citrátový cyklus účinky léků   MeSH
• deoxyglukosa toxicita   MeSH
• fluoracetáty toxicita   MeSH
• glykolýza účinky léků   MeSH
• malonáty toxicita   MeSH
• proteosyntéza účinky léků   MeSH
• pyruváty toxicita   MeSH
• reprodukovatelnost výsledků MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice metody   MeSH
• stav beztíže MeSH
• streptomycin toxicita   MeSH
• Synechococcus chemie   účinky léků   izolace a purifikace   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• antibakteriální látky MeSH
• antimycin A MeSH
• antimycin MeSH Prohlížeč
• azidy MeSH
• bromopyruvate MeSH Prohlížeč
• chloramfenikol MeSH
• deoxyglukosa MeSH
• fluoracetáty MeSH
• fluoroacetic acid MeSH Prohlížeč
• malonáty MeSH
• malonic acid MeSH Prohlížeč
• pyruváty MeSH
• streptomycin MeSH

A compound with promising anticancer properties, 3-bromopyruvate (3-BP) is a synthetic derivative of a pyruvate molecule; however, its toxicity in non-malignant cells has not yet been fully elucidated. Therefore, we elected to study the effects of 3-BP on primary hepatocytes in monolayer cultures, permeabilized hepatocytes and isolated mitochondria. After a 1-h treatment with 100 μM 3-BP cell viability of rat hepatocytes was decreased by 30 % as measured by the WST-1 test (p < 0.001); after 3-h exposure to ≥200 μM 3-BP lactate dehydrogenase leakage was increased (p < 0.001). Reactive oxygen species production was increased in the cell cultures after a 1-h treatment at concentrations ≥100 μmol/l (p < 0.01), and caspase 3 activity was increased after a 20-h incubation with 150 μM and 200 μM 3-BP (p < 0.001). This toxic effect of 3-BP was also proved using primary mouse hepatocytes. In isolated mitochondria, 3-BP induced a dose- and time-dependent decrease of mitochondrial membrane potential during a 10-min incubation both with Complex I substrates glutamate + malate or Complex II substrate succinate, although this decrease was more pronounced with the latter. We also measured the effect of 3-BP on respiration of isolated mitochondria. ADP-activated respiration was inhibited by 20 μM 3-BP within 10 min. Similar effects were also found in permeabilized hepatocytes of both species.

• Klíčová slova
• 3-bromopyruvate, Hepatocyte, Liver, Mitochondria, Toxicity,
• MeSH
• časové faktory MeSH
• hepatocyty cytologie   účinky léků   ultrastruktura   MeSH
• jaterní mitochondrie účinky léků   MeSH
• krysa rodu Rattus MeSH
• kultivované buňky MeSH
• membránový potenciál mitochondrií účinky léků   MeSH
• mitochondriální nemoci chemicky indukované   patofyziologie   MeSH
• myši MeSH
• pyruváty farmakologie   toxicita   MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• viabilita buněk účinky léků   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bromopyruvate MeSH Prohlížeč
• pyruváty MeSH
• reaktivní formy kyslíku MeSH