Isolation Of Thermophilic Bacteria Research Articles

Two new thermostable type II restriction endonucleases from Thermus aquaticus: TatI and TauI, which recognize the novel nucleotide sequences 5'-W (downward arrow)GTACW-3' and 5'-GCSG (downward arrow)C-3' respectively.

One hundred and forty isolates of thermophilic bacteria from the genus Thermus were screened for the presence of restriction endonuclease activity. Thermostable isoschizomers of restriction endonucleases, such as AceIII, BbvI, BglI, BsePI, FnuDII, HgiAI, MaeII, MboI, MseI, PvuII, StuI, TaqI, Tsp4CI, TspEI, XhoI and XmaIII, were isolated. Two restriction enzymes, TatI and TauI, recognizing novel degenerate sequences 5'-W (downward arrow)GTACW-3' and 5'-GCSG (downward arrow)C-3' respectively were partially purified and the recognition and cleavage sites were determined.

Two new thermostable type II restriction endonucleases from Thermus aquaticus: TatI and TauI, which recognize the novel nucleotide sequences 5′-W↓GTACW-3′ and 5′-GCSG↓C-3′ respectively

One hundred and forty isolates of thermophilic bacteria from the genus Thermus were screened for the presence of restriction endonuclease activity. Thermostable isoschizomers of restriction endonucleases, such as AceIII, BbvI, BglI, BsePI, FnuDII, HgiAI, MaeII, MboI, MseI, PvuII, StuI, TaqI, Tsp4CI, TspEI, XhoI and XmaIII, were isolated. Two restriction enzymes, TatI and TauI, recognizing novel degenerate sequences 5′-W↓GTACW-3′ and 5′-GCSG↓C-3′ respectively were partially purified and the recognition and cleavage sites were determined.

Novel thermophilic bacteria producing nitrile-degrading enzymes.

The first known report of the isolation of thermophilic bacteria which produce nitrile-degrading enzymes is presented. One of the strains isolated was studied in detail. Strain Dac521, classified as Bacillus pallidus, was capable of growth on acetonitrile, benzonitrile, propionitrile, acetamide, benzamide and propionamide as the sole carbon and nitrogen source in minimal nutrient media. The strain produced separate aliphatic-nitrile (e.g. acetonitrile)- and aromatic-nitrile (e.g. benzonitrile)-degrading activities. Acetonitrile-degrading activity was produced constitutively and enzyme production was not enhanced by the addition of substrate. Under conditions where benzonitrile was the sole carbon and nitrogen source in minimal nutrient media, acetonitrile-degrading enzyme activity was completely inhibited and benzonitrile-degrading activity was induced. Growth on substrates as sole carbon and nitrogen sources, together with the substrate specificity of cell-free extracts, suggested that acetonitrile and benzonitrile degradation may have occurred via nitrile hydratase and nitrilase pathways, respectively. Both the acetonitrile- and benzonitrile-degrading enzyme systems were significantly more thermostable in whole-cell preparations and cell-free extracts compared to their mesophilic counterparts.

Isolation of thermophilic bacteria using bacteriological grade agar at temperatures above 80 degrees C.

Isolation of thermophilic bacteria using bacteriological grade agar at temperatures above 80 degrees C.

The Next Iteration Factor (NIF) Method for Calculating Equilibrium Conditions in Subsurface Waters, for the Isolation of Microorganisms From Petroleum Reservoirs

A mathematically simple program, based on the next iteration factor (NIF) method, of calculating species concentrations in the 10-component system Na-K-Mg-Ca-Sr-H-Cl-SO4-OH-HCO3-CO3-CO2-BO2-H2O is presented. This method does not have the programming and convergence problems associated with established methods based on Newton- Raphson and free energy minimization techniques. We developed the new program in order to establish the physicochemical conditions of extreme environments, such as petroleum reservoirs, in which resident microorganisms may exist. The knowledge of the conditions that we obtained from these calculations has led to the isolation of thermophilic bacteria and archaea not previously recovered from deep subsurface environments such as petroleum reservoirs.

Two thermostable type II restriction endonucleases from Icelandic strains of the genus Thermus: Tsp4C I (ACN/GT), a novel type II restriction endonuclease, and Tsp8E I, an isoschizomer of the mesophilic enzyme Bgl I (GCCNNNN/NGGC)

Sixteen isolates of thermophilic bacteria from the genus Thermus, isolated from neutral and alkaline hot water springs in the southwest region of Iceland, were tested for the presence of restriction endonucleases. Extracts from five of the isolates showed evidence of the presence of restriction endonuclease activity by producing discrete nucleotide fragments when incubated at 65 degrees C with lambda phage DNA. Two of the isolates (Tsp4C and Tsp8E) were found to have particularly high levels of restriction endonuclease activity, and the respective enzymes from these two Thermus isolates were partially purified and characterized and their recognition and cleavage sites were determined. Enzyme Tsp4C I is a novel Type II restriction endonuclease recognizing the interrupted palindromic tetranucleotide sequence ACNGT, where N can be any one of the four bases in DNA. Tsp4C I, which retains full enzyme activity when incubated for 10 min at temperatures up to 76 degrees C, hydrolyses the phosphodiester bond in both strands of a double-stranded DNA substrate between the third and fourth bases of the recognition sequence (ACN/GT), generating fragments with a single base 3'-OH overhang. Enzyme Tsp8E I is a thermostable isoschizomer of the mesophilic Type II restriction endonuclease Bgl I (GCCNNNN/NGGC) [Lee, Clanton and Chirikjiam (1979) Fed. Proc. 28, 294], generating fragments with a three base 3'-OH overhang. However, unlike Bgl I, Tsp8E I exhibits considerable thermal stability, retaining full enzyme activity when incubated for 10 min at temperatures up to 78 degrees C. Both Tsp4C I and Tsp8E I represent significant additions to the small but expanding list of the extremely thermostable restriction endonucleases.

Isolation of five strains of thermophilic eubacteria in Antarctica

Five isolates of thermophilic bacteria, capable of growing at 65°C, were obtained from samples of soil collected from the Cryptogam Ridge (Mount Melbourne) and in the area north of Edmonson Point, Northern Victoria Land, Antarctica. Electron microscopy, morphological and physiological properties, lipid analyses and GC content of the isolates are described in this paper. On the basis of the results presented the organisms belong to the eubacterial domain.

Thermophilic Bacillus Species Associated with Phaeophyceae in the Arabian Gulf Shore Water at Kuwait

Thermophilic Bacillus species, associated with some brown algae from the Arabian Gulf at Kuwait, were investigated. Much higher population densities were recorded from algal surfaces (the phycoplanes) than from the surrounding sea-water. The filamentous algae (Scytosiphon and Ectocarpus) stimulated the development of larger bacterial populations more than the membranous forms (Cystoseira, Sargassum, Colpomenia, and Padina). 102 isolates of thermophilic bacteria were isolated from the different phycoplanes and from sea-water. They were identified as: Bacillus stearothermophilus (54 strains), B. coagulans (36 strains), and B. brevis (12 strains). Investigation of the growth requirements of these Bacillus species at 55°C showed that for 31 isolates the addition of yeast extract and/or sea-water to Czapek-Dox agar medium was required. According to their growth on Czapek-Dox, Czapek-Dox sea-water, and/or Czapek-Dox yeast-extract agar media they could be grouped into 6 different growth requirements. Results of specific vitamin requirements showed variations according to the specific algal phycoplane. According to their vitamin requirements the Bacillus species could be divided into 17 groups. Folic acid and β-aminobenzoic acid were most frequently required, while biotin, pyridoxin, and riboflavin were required occasionally. Im Seewasser des arabischen Golfes wurden thermophile Bacillus-Arten, hinsichtlich einer möglichen Assoziation mit Braunalgen untersucht. Auf der Algenoberfläche wurden wesentlich höhere Populationsdichten festgestellt als im Seewasser der Umgebung. Fadenbildende Algen (Scytosiphon und Ectocarpus) stimulierten die Entwicklung größerer bakterieller Populationen mehr als membranbildende Formen (Cystoseira, Sargassum, Colpomenia und Padina). Von den Algen sowie aus dem Seewasser wurden 102 Isolate thermophiler Bakterien gewonnen. Sie wurden identifiziert als: Bacillus stearothermophilus (54 Stämme), B. coagulans (36 Stämme) und B. brevis (12 Stämme). 31 Isolate benötigten für ihr Wachstum (55°C) Hefeextrakt- und/oder Seewasserzusatz zum Czapek-Dox-Agar. An Hand dieser Zusätze konnten sie in 6 Gruppen mit unterschiedlichen Nährstoffansprüchen unterteilt werden. Der Vitaminbedarf der Bacillus-Arten war von Alge zu Alge, von der sie jeweils isoliert worden waren, verschieden. Je nach Vitaminbedarf war eine Unterteilung in 17 Gruppen möglich. Folsäure und p-Aminobenzoesäure wurden sehr häufig, Biotin, Pyridoxin und Riboflavin hingegen nur gelegentlich benötigt.