Stereochemical course of hydrolysis of DNA by exonuclease I from Escherichia coli

Biochemistry ◽  
1985 ◽  
Vol 24 (8) ◽  
pp. 2072-2076 ◽  
Author(s):  
Richard S. Brody ◽  
Kevin G. Doherty
Keyword(s):  
Escherichia Coli ◽  
Exonuclease I ◽  
Hydrolysis Of ◽  
Hydrolysis Of Dna

scholarly journals Nucleases Encoded by the Integrated Elements CJIE2 and CJIE4 Inhibit Natural Transformation of Campylobacter jejuni

2009 ◽  
Vol 192 (4) ◽  
pp. 936-941 ◽  
Author(s):  
Esther J. Gaasbeek ◽  
Jaap A. Wagenaar ◽  
Magalie R. Guilhabert ◽  
Jos P. M. van Putten ◽  
Craig T. Parker ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Campylobacter Jejuni ◽  
Genetic Factors ◽  
Natural Transformation ◽  
Homologous Gene ◽  
Dna Uptake ◽  
Dna Arrays ◽  
Genetic Transfer ◽  
Hydrolysis Of ◽  
Hydrolysis Of Dna

ABSTRACT The species Campylobacter jejuni is naturally competent for DNA uptake; nevertheless, nonnaturally transformable strains do exist. For a subset of strains we previously showed that a periplasmic DNase, encoded by dns, inhibits natural transformation in C. jejuni. In the present study, genetic factors coding for DNase activity in the absence of dns were identified. DNA arrays indicated that nonnaturally transformable dns-negative strains contain putative DNA/RNA nonspecific endonucleases encoded by CJE0566 and CJE1441 of strain RM1221. These genes are located on C. jejuni integrated elements 2 and 4. Expression of CJE0566 and CJE1441 from strain RM1221 and a homologous gene from strain 07479 in DNase-negative Escherichia coli and C. jejuni strains indicated that these genes code for DNases. Genetic transfer of the genes to a naturally transformable C. jejuni strain resulted in a decreased efficiency of natural transformation. Modeling suggests that the C. jejuni DNases belong to the Serratia nuclease family. Overall, the data indicate that the acquisition of prophage-encoded DNA/RNA nonspecific endonucleases inhibits the natural transformability of C. jejuni through hydrolysis of DNA.

scholarly journals GES-2, a Class A β-Lactamase fromPseudomonas aeruginosa with Increased Hydrolysis of Imipenem

2001 ◽  
Vol 45 (9) ◽  
pp. 2598-2603 ◽  
Author(s):  
Laurent Poirel ◽  
Gerhard F. Weldhagen ◽  
Thierry Naas ◽  
Christophe De Champs ◽  
Michael G. Dove ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Amino Acid ◽  
Amino Acid Change ◽  
Blood Cultures ◽  
Class A ◽  
Omega Loop ◽  
Cephalosporin Resistance ◽  
Lactamase Gene ◽  
Hydrolysis Of

ABSTRACT Pseudomonas aeruginosa GW-1 was isolated in 2000 in South Africa from blood cultures of a 38-year-old female who developed nosocomial pneumonia. This isolate harbored a self-transferable ca. 100-kb plasmid that conferred an expanded-spectrum cephalosporin resistance profile associated with an intermediate susceptibility to imipenem. A β-lactamase gene, bla GES-2, was cloned from whole-cell DNA of P. aeruginosa GW-1 and expressed in Escherichia coli. GES-2, with a pI value of 5.8, hydrolyzed expanded-spectrum cephalosporins, and its substrate profile was extended to include imipenem compared to that of GES-1, identified previously in Klebsiella pneumoniae. GES-2 activity was less inhibited by clavulanic acid, tazobactam and imipenem than GES-1. The GES-2 amino acid sequence differs from that of GES-1 by a glycine-to-asparagine substitution in position 170 located in the omega loop of Ambler class A enzymes. This amino acid change may explain the extension of the substrate profile of the plasmid-encoded β-lactamase GES-2.

Hydrolysis of organophosphate triesters by Escherichia coli aminopeptidase P

2004 ◽  
Vol 27 (1) ◽  
pp. 7-12 ◽  
Author(s):  
Shu-Chuan Jao ◽  
Li-Fang Huang ◽  
Ying Shin Tao ◽  
Wen-Shan Li
Keyword(s):  
Escherichia Coli ◽  
Aminopeptidase P ◽  
Organophosphate Triesters ◽  
Hydrolysis Of

Hidrolisis minyak biji asam jawa (tamarindus indica linn) menjadi asam lemaknya dan uji aktivitas antibakteri

2021 ◽  
Vol 2 (2) ◽  
pp. 100-104
Author(s):  
Arnanda Dhafin Rizky ◽  
Sutrisno Sutrisno ◽  
Parlan Parlan
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Fatty Acid ◽  
Potassium Hydroxide ◽  
Seed Oil ◽  
Acid Number ◽  
Moderate Intensity ◽  
Tamarindus Indica ◽  
Tamarind Seed ◽  
Hydrolysis Of

Saponification tamarind seed oil used potassium hydroxide and acidification with hydrochloric acid is produced fatty acid in the form of soft white solid, has melting point 50-55 degrees celcius. The result of this hydrolysis positive test of unsaturation. It has an acid number of 115.36, saponification number of 114.80, and iodine number of 53.34. The success of hydrolysis of oil into fatty acid is characterized by identification of IR spectra showing O-H vibration with moderate intensity and widening, C=O vibration of carboxylic acid with strong intensity. Fatty acids of tamarind seed have the potential as antibacterial to test bacteria Staphylococcus aureus and Escherichia coli with diameter respectively 7.31 mm and 7.58 mm. Minyak biji asam jawa yang disaponifikasi menggunakan kalium hidroksida dan pengasaman dengan asam klorida dihasilkan asam lemak berupa padatan lunak berwana putih, memiliki titik lebur 50-55 derajat celcius. hasil hidrolisis ini positif uji ketidakjenuhan, bilangan asam 115,36, bilangan penyabunan 114,80, dan bilangan iod 53,34. Keberhasilan hidrolisis minyak menjadi asam lemak ditandai dari identifikasi spektrum IR yang menunjukkan vibrasi ulur O-H dengan intensitas sedang dan melebar serta vibrasi ulur C=O asam karboksilat dengan intensitas kuat. Asam lemak biji asam jawa berpotensi sebagai antibakteri terhadap bakteri uji Staphylococcus aureus dan Escherichia coli dengan zona hambat masing-masing 7,31 mm dan 7,58 mm.

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