Naslov
Growth and phosphorylation profiles in S. rimosus, oxytetracycline producer strains

Autori
Šarić, Ela ; Quinn, Gerre ; Šemanjski, Maja ; Paradžik, Tina ; Jurin, Mladenka ; Hunter, Iain ; Herron, Paul ; Maček, Boris ; Vujaklija, Dušica

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
Internal programme book of 1st School of Proteomics / - , 2017, 24-24

Skup
1st European School on Practical Proteomics

Mjesto i datum
Split, Hrvatska, 08.10.2017. - 12.10.2017

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
phosphorylation ; S. rimosus ; OTC production

Sažetak
Streptomyces are prokaryotic filamentous bacteria predominantly found in soil that exhibit a tightly regulated and complex life cycle. It has been estimated that 2/3 of clinically relevant antibiotics are produced by Streptomycetes. During their multicellular development Streptomyces species produce many natural products, amongst which are the best known bioactive compounds such as broad- spectrum antibiotics (tetracyclines, streptomycins and β-lactams), immunosuppressants (rapamycin) and anticancer drugs (doxorubicin). Among these natural products, tetracyclines (TCs) belong to one of the most clinically and commercially significant class of antibiotics. Streptomyces rimosus is best known strain of oxytetracycline (OTC) producers. It has been reported that phosphorylation plays an important regulatory role in metabolism and antibiotic production in Streptomyces. Analysis of the S. rimosus genome has predicted 33 eukaryotic-like protein kinases and 27 eukaryotic type protein phosphatases in this species. We hypothesized that OTC production in S. rimosus may be triggered by posttranslational modifications in some regulatory proteins. In order to identify these key proteins we measured the production of OTC in various strains of Streptomyces using HPLC. Additionally, we examined the phosphorylation pattern during growth of these strains by Western blot, whilst the morphology of mycelia was observed by fluorescence microscopy. Our observations indicated that the Streptomyces strains had variations in OTC production, whereas Western blot analyses showed different phosphorylation patterns for each strain. Images from confocal microscopy revealed different viability and morphological features. From these strains, we selected the most consistently optimal producer of OTC and used this to perform phosphoproteomic analyses using high accuracy mass spectrometry. Our preliminary results revealed a differential expression of the proteome/phosphoproteome at different stages of Streptomyces growth. Further analysis of these proteomic results is still in progress. Growth curves in each S. rimosus strain demonstrated that bacteria show stagnation in growth during the exponential phase which is called the ‘decision’ phase (indicated by red circles). After this phase, bacteria start to produce antibiotic. Three different stages of growth were chosen for phosphoproteome analysis.

Izvorni jezik
Engleski

Znanstvena područja
Biologija

POVEZANOST RADA