A .beta.-elimination reaction involving a binuclear ethylplatinum(II) complex

1982 ◽  
Vol 1 (9) ◽  
pp. 1183-1188 ◽  
Author(s):  
Kazi A. Azam ◽  
Michael P. Brown ◽  
Susan J. Cooper ◽  
Richard J. Puddephatt
Keyword(s):  
Elimination Reaction ◽  
Beta Elimination

A first-order base-initiated .beta.-elimination reaction involving a carbanion intermediate

1970 ◽  
Vol 92 (20) ◽  
pp. 5945-5949 ◽  
Author(s):  
Frederick G. Bordwell ◽  
Kwok-Chun. Yee ◽  
A. C. Knipe
Keyword(s):  
Elimination Reaction ◽  
First Order ◽  
Beta Elimination

scholarly journals Bacteriophage-T4 and Micrococcus luteus UV endonucleases are not endonucleases but β-elimination and sometimes βδ-elimination catalysts

1989 ◽  
Vol 259 (3) ◽  
pp. 751-759 ◽  
Author(s):  
V Bailly ◽  
B Sente ◽  
W G Verly
Keyword(s):  
Enzyme Preparation ◽  
Micrococcus Luteus ◽  
Bacteriophage T4 ◽  
Pyrimidine Dimer ◽  
Elimination Reaction ◽  
Ap Sites ◽  
Beta Elimination ◽  
Ap Site ◽  
Polynucleotide Chain

Bacteriophage-T4 UV endonuclease nicks the C(3′)-O-P bond 3′ to AP (apurinic or apyrimidinic) sites by a beta-elimination reaction. The breakage of this bond is sometimes followed by the nicking of the C(5′)-O-P bond 5′ to the AP site, leaving a 3′-phosphate end; delta-elimination is proposed as a mechanism to explain this second reaction. The AP site formed when this enzyme acts on a pyrimidine dimer in a polynucleotide chain undergoes the same nicking reactions. Micrococcus luteus UV endonuclease also nicks the C(3′)-O-P bond 3′ to AP sites by a beta-elimination reaction. No subsequent delta-elimination was observed, but this might be due to the presence of 2-mercaptoethanol in the enzyme preparation.

ChemInform Abstract: THE BASE-INDUCED BETA-ELIMINATION REACTION OF 1,1,1-TRISUBSTITUTED HYDRAZINIUM SALTS

1974 ◽  
Vol 5 (37) ◽  
pp. no-no
Author(s):  
Y. TAMURA ◽  
J. MINAMIKAWA ◽  
O. NISHIKAWA ◽  
M. IKEDA
Keyword(s):  
Elimination Reaction ◽  
Beta Elimination ◽  
Hydrazinium Salts

UV endonuclease V from bacteriophage T4 catalyzes DNA strand cleavage at aldehydic abasic sites by a syn .beta.-elimination reaction

1989 ◽  
Vol 111 (20) ◽  
pp. 8029-8030 ◽  
Author(s):  
Abhijit Mazumder ◽  
John A. Gerlt ◽  
Lois Rabow ◽  
Michael J. Absalon ◽  
JoAnne Stubbe ◽  
...  
Keyword(s):  
Bacteriophage T4 ◽  
Elimination Reaction ◽  
Abasic Sites ◽  
Endonuclease V ◽  
Beta Elimination ◽  
Dna Strand

scholarly journals Mechanism of DNA strand nicking at apurinic/apyrimidinic sites by Escherichia coli [formamidopyrimidine]DNA glycosylase

1989 ◽  
Vol 262 (2) ◽  
pp. 581-589 ◽  
Author(s):  
V Bailly ◽  
W G Verly ◽  
T O'Connor ◽  
J Laval
Keyword(s):  
Escherichia Coli ◽  
Dna Glycosylase ◽  
Elimination Reaction ◽  
Phosphodiester Bonds ◽  
Beta Elimination ◽  
Dna Strand

Escherichia coli [formamidopyrimidine]DNA glycosylase catalyses the nicking of both the phosphodiester bonds 3′ and 5′ of apurinic or apyrimidinic sites in DNA so that the base-free deoxyribose is replaced by a gap limited by 3′-phosphate and 5′-phosphate ends. The two nickings are not the results of hydrolytic processes; the [formamidopyrimidine]DNA glycosylase rather catalyses a beta-elimination reaction that is immediately followed by a delta-elimination. The enzyme is without action on a 3′-terminal base-free deoxyribose or on a 3′-terminal base-free unsaturated sugar produced by a beta-elimination reaction nicking the DNA strand 3′ to an apurinic or apyrimidinic site.

scholarly journals The multiple activities of Escherichia coli endonuclease IV and the extreme lability of 5′-terminal base-free deoxyribose 5-phosphates

1989 ◽  
Vol 259 (3) ◽  
pp. 761-768 ◽  
Author(s):  
V Bailly ◽  
W G Verly
Keyword(s):  
Escherichia Coli ◽  
Dna Polymerase ◽  
Rat Liver ◽  
Half Life ◽  
Elimination Reaction ◽  
Ap Endonuclease ◽  
Exonuclease Iii ◽  
E Coli ◽  
Beta Elimination ◽  
Ap Site

Escherichia coli endonuclease IV hydrolyses the C(3′)-O-P bond 5′ to a 3′-terminal base-free deoxyribose. It also hydrolyses the C(3′)-O-P bond 5′ to a 3′-terminal base-free 2′,3′-unsaturated sugar produced by nicking 3′ to an AP (apurinic or apyrimidinic) site by beta-elimination; this explains why the unproductive end produced by beta-elimination is converted by the enzyme into a 3′-OH end able to prime DNA synthesis. The action of E. coli endonuclease IV on an internal AP site is more complex: in a first step the C(3′)-O-P bond 5′ to the AP site is hydrolysed, but in a second step the 5′-terminal base-free deoxyribose 5′-phosphate is lost. This loss is due to a spontaneous beta-elimination reaction in which the enzyme plays no role. The extreme lability of the C(3′)-O-P bond 3′ to a 5′-terminal AP site contrasts with the relative stability of the same bond 3′ to an internal AP site; in the absence of beta-elimination catalysts, at 37 degrees C the half-life of the former is about 2 h and that of the latter 200 h. The extreme lability of a 5′-terminal AP site means that, after nicking 5′ to an AP site with an AP endonuclease, in principle no 5′----3′ exonuclease is needed to excise the AP site: it falls off spontaneously. We have repaired DNA containing AP sites with an AP endonuclease (E. coli endonuclease IV or the chromatin AP endonuclease from rat liver), a DNA polymerase devoid of 5′----3′ exonuclease activity (Klenow polymerase or rat liver DNA polymerase beta) and a DNA ligase. Catalysts of beta-elimination, such as spermine, can drastically shorten the already brief half-life of a 5′-terminal AP site; it is what very probably happens in the chromatin of eukaryotic cells. E. coli endonuclease IV also probably participates in the repair of strand breaks produced by ionizing radiations: as E. coli endonuclease VI/exonuclease III, it is a 3′-phosphoglycollatase and also a 3′-phosphatase. The 3′-phosphatase activity of E. coli endonuclease VI/exonuclease III and E. coli endonuclease IV can also be useful when the AP site has been excised by a beta delta-elimination reaction.

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