Fourier kızılötesi dönüşüm spektroskopi tekniği ile bakteri karakterizasyonu


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Biyolojik Bilimler Bölümü, Türkiye

Tezin Onay Tarihi: 2005

Tezin Dili: İngilizce

Öğrenci: Şebnem Garip

Danışman: FERİDE SEVERCAN

Özet:

New and rapid techniques for the characterization and identification of bacteria would have an important role in clinical microbiology and in food analysis because of an increasing prevalence of infectious diseases and In this work we carried out two approaches. In the first study the characterization and differentiation of mesophilic and thermophilic bacteria were investigated by using Fourier Transform Infrared (FTIR) Spectroscopic technique. In the second study, we investigated the characterization and identification of 3 Bacillus and Micrococcus species Our results from first approach show that there was a dramatic difference between mesophilic and thermophilic bacteria. The protein concentration was high, lipid concentration, the level of triglycerides and the unsaturated acyl chains decreased in thermophilic bacteria. We found that in thermophilic bacteria PO- 2 groups become hydrogen bounded. In addition, our results suggest that the cellular DNA content was low in thermophilic bacteria. Moreover there were characteristic peaks for both mesophilic and thermophilic bacteria and these peaks can be used for the differentiation of these two bacteria group. There were also some specific peaks that can be used for the differentiation of Escherichia coli and Lactobacillus plantarum at species level. In the second approach, our results show that there were significant spectral differences between Bacillus and Micrococcus species such as the proportion of unsaturated acyl chains in triglycerides were higher in Micrococcus species. Moreover we observed different bands that may be explained by an acetate oxidation via the tricarboxylic acid cycle and an exopolymer formation in Micrococcus species. In addition to that another band similar to glycogen, may be explained by a glycogen-like storage material in Micrococcus species. Also there are characteristic peaks that can be used for identification of Micrococcus spp.