scholarly journals Error-Prone Processing of Apurinic/Apyrimidinic (AP) Sites by PolX Underlies a Novel Mechanism That Promotes Adaptive Mutagenesis in Bacillus subtilis

2014 ◽  
Vol 196 (16) ◽  
pp. 3012-3022 ◽  
Author(s):  
R. d. C. Barajas-Ornelas ◽  
F. H. Ramirez-Guadiana ◽  
R. Juarez-Godinez ◽  
V. M. Ayala-Garcia ◽  
E. A. Robleto ◽  
...  
2006 ◽  
Vol 188 (21) ◽  
pp. 7512-7520 ◽  
Author(s):  
Christian Ross ◽  
Christine Pybus ◽  
Mario Pedraza-Reyes ◽  
Huang-Mo Sung ◽  
Ronald E. Yasbin ◽  
...  

ABSTRACT Previously, using a chromosomal reversion assay system, we established that an adaptive mutagenic process occurs in nongrowing Bacillus subtilis cells under stress, and we demonstrated that multiple mechanisms are involved in generating these mutations (41, 43). In an attempt to delineate how these mutations are generated, we began an investigation into whether or not transcription and transcription-associated proteins influence adaptive mutagenesis. In B. subtilis, the Mfd protein (transcription repair coupling factor) facilitates removal of RNA polymerase stalled at transcriptional blockages and recruitment of repair proteins to DNA lesions on the transcribed strand. Here we demonstrate that the loss of Mfd has a depressive effect on stationary-phase mutagenesis. An association between Mfd mutagenesis and aspects of transcription is discussed.


2011 ◽  
Vol 40 (2) ◽  
pp. 739-750 ◽  
Author(s):  
Christopher Collier ◽  
Cristina Machón ◽  
Geoff S. Briggs ◽  
Wiep Klaas Smits ◽  
Panos Soultanas

2005 ◽  
Vol 187 (21) ◽  
pp. 7374-7381 ◽  
Author(s):  
José M. Salas-Pacheco ◽  
Barbara Setlow ◽  
Peter Setlow ◽  
Mario Pedraza-Reyes

ABSTRACT The Bacillus subtilis enzymes ExoA and Nfo (originally termed YqfS) are endonucleases that can repair apurinic/apyrimidinic (AP) sites and strand breaks in DNA. We have analyzed how the lack of ExoA and Nfo affects the resistance of growing cells and dormant spores of B. subtilis to a variety of treatments, some of which generate AP sites and DNA strand breaks. The lack of ExoA and Nfo sensitized spores (termed α−β−) lacking the majority of their DNA-protective α/β-type small, acid-soluble spore proteins (SASP) to wet heat. However, the lack of these enzymes had no effect on the wet-heat resistance of spores that retained α/β-type SASP. The lack of either ExoA or Nfo sensitized wild-type spores to dry heat, but loss of both proteins was necessary to sensitize α−β− spores to dry heat. The lack of ExoA and Nfo also sensitized α−β−, but not wild-type, spores to desiccation. In contrast, loss of ExoA and Nfo did not sensitize growing cells or wild-type or α−β− spores to hydrogen peroxide or t-butylhydroperoxide. Loss of ExoA and Nfo also did not increase the spontaneous mutation frequency of growing cells. exoA expression took place not only in growing cells, but also in the forespore compartment of the sporulating cell. These results, together with those from previous work, suggest that ExoA and Nfo are additional factors that protect B. subtilis spores from DNA damage accumulated during spore dormancy.


2003 ◽  
Vol 185 (18) ◽  
pp. 5380-5390 ◽  
Author(s):  
José M. Salas-Pacheco ◽  
Norma Urtiz-Estrada ◽  
Guadalupe Martínez-Cadena ◽  
Ronald E. Yasbin ◽  
Mario Pedraza-Reyes

ABSTRACT The enzymatic properties and the physiological function of the type IV apurinic/apyrimidinic (AP)-endonuclease homolog of Bacillus subtilis, encoded by yqfS, a gene specifically expressed in spores, were studied here. To this end, a recombinant YqfS protein containing an N-terminal His6 tag was synthesized in Escherichia coli and purified to homogeneity. An anti-His6-YqfS polyclonal antibody exclusively localized YqfS in cell extracts prepared from B. subtilis spores. The His6-YqfS protein demonstrated enzymatic properties characteristic of the type IV family of DNA repair enzymes, such as AP-endonucleases and 3′-phosphatases. However, the purified protein lacked both 5′-phosphatase and exonuclease III activities. YqfS showed not only a high level of amino acid identity with E. coli Nfo but also a high resistance to inactivation by EDTA, in the presence of DNA containing AP sites (AP-DNA). These results suggest that YqfS possesses a trinuclear Zn center in which the three metal atoms are intimately coordinated by nine conserved basic residues and two water molecules. Electrophoretic mobility shift assays demonstrated that YqfS possesses structural properties that permit it to bind and scan undamaged DNA as well as to strongly interact with AP-DNA. The ability of yqfS to genetically complement the DNA repair deficiency of an E. coli mutant lacking the major AP-endonucleases Nfo and exonuclease III strongly suggests that its product confers protection to cells against the deleterious effects of oxidative promoters and alkylating agents. Thus, we conclude that YqfS of B. subtilis is a spore-specific protein that has structural and enzymatic properties required to participate in the repair of AP sites and 3′ blocking groups of DNA generated during both spore dormancy and germination.


Author(s):  
Dwight Anderson ◽  
Charlene Peterson ◽  
Gursaran Notani ◽  
Bernard Reilly

The protein product of cistron 3 of Bacillus subtilis bacteriophage Ø29 is essential for viral DNA synthesis and is covalently bound to the 5’-termini of the Ø29 DNA. When the DNA-protein complex is cleaved with a restriction endonuclease, the protein is bound to the two terminal fragments. The 28,000 dalton protein can be visualized by electron microscopy as a small dot and often is seen only when two ends are in apposition as in multimers or in glutaraldehyde-fixed aggregates. We sought to improve the visibility of these small proteins by use of antibody labeling.


Planta Medica ◽  
2008 ◽  
Vol 74 (09) ◽  
Author(s):  
N Padilla-Montaño ◽  
IL Bazzocchi ◽  
L Moujir

2018 ◽  
Vol 22 (02) ◽  
pp. 82-89
Author(s):  
Friedrich von Rheinbaben ◽  
Oliver Riebe ◽  
Johanna Köhnlein ◽  
Sebastian Werner

ZusammenfassungZentrales Bauteil des Genius® 90 Therapie Systems ist der sogenannte Genius-Tank, dem die frische Dialyseflüssigkeit entnommen und in den die verbrauchte Lösung nach der Dialyse zurückgeführt wird. Daher kommt der sicheren Aufbereitung des Systems eine besondere Bedeutung zu. Hierfür wird ein Aufbereitungsverfahren unter Verwendung von UV-Licht in Kombination mit einem chemischen Desinfektionsmittel angewendet. Ziel der hier beschriebenen Untersuchung war es, die Wirkungsbreite und Wirkungstiefe dieses Aufbereitungsverfahrens unter praxisnahen Phase-3-Bedingungen zu ermitteln. Dazu wurde das Gerät mit Mikroorganismen und Viren künstlich kontaminiert und die Wirkung der einzelnen Verfahrensschritte ermittelt. Im Gegensatz zu der üblichen Vorgehensweise praxisnaher Untersuchungen machen Aufbereitungsverfahren medizinischer Geräte unter Phase-3-Kriterien meist eine neuartige Arbeitsweise erforderlich – im Falle der hier vorgestellten Untersuchung sogar die Konstruktion eines speziellen Geräts zur Platzierung von Keimträgen im Genius-Tank. Im Ergebnis konnte gezeigt werden, dass bereits UV-Licht allein sowie in Kombination mit einem chemischen Desinfektionsmittel unter praxisnahen Bedingungen eine sichere Wirksamkeit gegen Bakterien (Pseudomonas aeruginosa) und bakterielle Sporen (Bacillus subtilis), Schimmelpilze (Aspergillus brasiliensis) und Viren (Murines Parvovirus) besitzt.


Planta Medica ◽  
2007 ◽  
Vol 73 (09) ◽  
Author(s):  
L Moujir ◽  
L de León ◽  
IL Bazzocchi

2020 ◽  
Vol 21 (1) ◽  
pp. 14-19
Author(s):  
Praptiningsih Gamawati Adinurani ◽  
Sri Rahayu ◽  
Nurul Fima Zahroh

Mikroba Bacillus subtilis merupakan agen pengendali hayati mempunyai kelebihan sebagai Plant Growth Promoting Rhizobacteria (PGPR) yaitu dapat berfungsi sebagai biofertilizer, biostimulan, biodekomposer dan bioprotektan. Tujuan penelitian mengetahui potensi B. subtilis dalam merombak bahan organik sebagai usaha meningkatkan ketersediaan bahan organik tanah yang semakin menurun. Penelitian menggunakan Rancangan Petak Terbagi dengan berbagai  bahan organik sebagai petak utama (B0 = tanpa bahan organik, B1 = kotoran ayam,  B2 = kotoran kambing, B3 = kotoran sapi) dan aplikasi B.subtilis sebagai anak petak (A0 = 0 cc/L, A1 = 5cc/L, A2 = 10 cc/L, Pengamatan meliputi variabel tinggi tanaman, indeks luas daun, jumlah buah per tanaman, berat buah per tanaman, dan bahan organik tanah. Data pengamatan  dianalisis ragam  menggunakan  Statistical Product and Service Solutions (SPSS) versi 25 dan dilanjutkan dengan uji Duncan untuk mengetahui signifikansi perbedaan antar perlakuan. Hasil penelitian menunjukkan tidak terdapat interaksi antara bahan organik kotoran ternak dan konsentrasi B. subtilis terhadap semua variabel pengamatan. Potensi B. subtilis sangat baik dalam mendekomposisi bahan organik yang ditunjukkan dengan peningkatan bahan organik, dan hasil terbaik pada kotoran  sapi (B3) dan konsentrasi B. subtilis 15 mL/L masing-masing sebesar 46.47 % dan 34.76 %. Variabel pertumbuhan tidak berbeda nyata kecuali tinggi tanaman dengan pertambahan tinggi paling banyak pada pemberian kotoran kambing sebesar 170.69 %.


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