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Characterization of the ABC-F protein Sco0636 in Streptomyces coelicolor
Pinďáková, Nikola ; Balíková Novotná, Gabriela (advisor) ; Mikušová, Gabriela (referee)
The main topic of this diploma thesis is ARE (resistance) proteins from the ABC-F family of the second class of ABC proteins. ARE proteins confer resistance to antibiotics that bind to a large ribosomal subunit and therefore inhibit proteosynthesis. One of the ARE proteins is the Lmr (C) protein, which is part of the linkomycin biosynthesis cluster of Streptomyces lincolnensis, and according to new results, Lmr (C) does not have to be just resistant protein but may have also regulatory function. We decided to study Sco0636, the closest homologue to Lmr (C) in Streptomyces coelicolor, which is a model organism in the study of secondary metabolism. Thanks to the production of color pigments, it is possible to monitor the effect of ARE proteins on secondary metabolism directly on the plates. I prepared the deletion mutant and the strain with constitutive expression of sco0636, and observed the effect on the phenotype. I followed the production of a blue asset and set a minimum inhibitory concentration to selected antibiotics, which bind to the ribosome. I have found that Sco0636 gives high resistance to tiamulin and so it has been named TiaA. The deletion of gene sco0636 accelerated production of actinorodine, and constitutive expression of this gene slowed down production. Keywords: ABC proteins,...
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Characterization of the ABC-F protein Sco0636 in Streptomyces coelicolor
Pinďáková, Nikola ; Balíková Novotná, Gabriela (advisor) ; Mikušová, Gabriela (referee)
The main topic of this diploma thesis is ARE (resistance) proteins from the ABC-F family of the second class of ABC proteins. ARE proteins confer resistance to antibiotics that bind to a large ribosomal subunit and therefore inhibit proteosynthesis. One of the ARE proteins is the Lmr (C) protein, which is part of the linkomycin biosynthesis cluster of Streptomyces lincolnensis, and according to new results, Lmr (C) does not have to be just resistant protein but may have also regulatory function. We decided to study Sco0636, the closest homologue to Lmr (C) in Streptomyces coelicolor, which is a model organism in the study of secondary metabolism. Thanks to the production of color pigments, it is possible to monitor the effect of ARE proteins on secondary metabolism directly on the plates. I prepared the deletion mutant and the strain with constitutive expression of sco0636, and observed the effect on the phenotype. I followed the production of a blue asset and set a minimum inhibitory concentration to selected antibiotics, which bind to the ribosome. I have found that Sco0636 gives high resistance to tiamulin and so it has been named TiaA. The deletion of gene sco0636 accelerated production of actinorodine, and constitutive expression of this gene slowed down production. Keywords: ABC proteins,...
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Detection of Streptococcus agalactiae in pregnant women and newborns
HÁLOVÁ, Eliška
S. agalactiae are common commensals of the nasopharynx, vagina and gastrointestinal tract. Now digestive tract is considered a very likely source of vaginal colonization. Colonization by the bacteria is in many cases asymptomatic. S. agalactiae causes a variety of infections in neonates and is a leading cause of neonatal morbidity and mortality. Transmission takes place vertically from colonized mother to fetus. A potential source of GBS infections may also be mother's milk. This type of transmission is very rare. S. agalactiae infection induces not only in neonates but also in adults, particularly in older persons and persons with other ongoing disease. In the theoretical part, I focused on the current knowledge about S. agalactiae, neonatal GBS infections and their prevention options. Then I assess current possibilities of identification and diagnostics of S. agalactiae, including the determination of antibiotic susceptibility. I outlined the current situation of the increasing resistance of S. agalactiae to macrolides and lincosamides and described the situation in several different countries. The practical part is performed on bacteriological department Ceske Budejovice Hospital, a.s. where I dealt with the whole process of identification and diagnostics of S. agalactiae. Firstly I did cultivate, or also preparing specimens for microscopic evaluation. I also identified S. agalactiae using CAMP assay, latex agglutination method or MALDI - TOF. For strains identified as S. agalactiae was performed for antibiotic sensitivity by the disc diffusion test. All the work I carried out under the supervision of the head of his thesis and laboratory staff according to standard operating procedures. Part of my work is devoted to the results. Their statistical processing, I found the colonization by S. agalactiae in a population of pregnant women. I also concentrated on the distribution of individual serotypes of this bacterium in newborns. For each strain isolated from pregnant women and infants I assess its sensitivity to penicillin, ampicillin, erythromycin and clindamycin. The practice in the laboratory showed that the most frequently used methods for identification of S. agalactiae are CAMP test and MALDI - TOF mass spectrometry. Latex agglutination today too often used.
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