Please wait, while we are loading the content...
Please wait, while we are loading the content...
| Content Provider | PubMed Central |
|---|---|
| Author | Hevroni, D. Livneh, Z. |
| Abstract | Mutations produced in Escherichia coli by apurinic sites are believed to arise via SOS-assisted translesion replication. Analysis of replication products synthesized on depurinated single-stranded DNA by DNA polymerase III holoenzyme revealed that apurinic sites frequently blocked in vitro replication. Bypass frequency of an apurinic site was estimated to be 10-15%. Direct evidence for replicative bypass was obtained in a complete single-stranded----replicative form replication system containing DNA polymerase III holoenzyme, single-stranded DNA binding protein, DNA polymerase I, and DNa ligase, by demonstrating the sensitivity of fully replicated products to the apurinic endonuclease activity of E. coli exonuclease III. Termination at apurinic sites, like termination at pyrimidine photodimers, involved dissociation of the polymerase from the blocked termini, followed by initiations at available primer templates. When no regular primer templates were available, the polymerase underwent repeated cycles of dissociation and rebinding at the blocked termini and, while bound, carried out multiple polymerization-excision reactions opposite the apurinic sites, leading to turnover of dNTPs into dNMPs. From the in vitro turnover rates, we could predict with striking accuracy the specificity of apurinic site mutagenesis, as determined in vivo in depurinated single-stranded DNA from an M13-lac hybrid phage. This finding is consistent with the view that DNA polymerase III holoenzyme carries out the mutagenic "misinsertion" step during apurinic site mutagenesis in vivo and that the specificity of the process is determined primarily by the polymerase. SOS-induced proteins such as UmuD/C might act as processivity-like factors to stabilize the polymerase-DNA complex, thus increasing the efficiency of the next stage of past-lesion polymerization required to complete the bypass reaction. |
| Starting Page | 5046 |
| File Format | |
| ISSN | 10916490 |
| e-ISSN | 10916490 |
| Journal | Proceedings of the National Academy of Sciences of the United States of America |
| Issue Number | 14 |
| Volume Number | 85 |
| Language | English |
| Publisher Date | 1988-07-01 |
| Access Restriction | Open |
| Subject Keyword | Research in Higher Education |
| Content Type | Text |
| Resource Type | Article |
| Subject | Multidisciplinary |
National Digital Library of India (NDLI) is a virtual repository of learning resources which is not just a repository with search/browse facilities but provides a host of services for the learner community. It is sponsored and mentored by Ministry of Education, Government of India, through its National Mission on Education through Information and Communication Technology (NMEICT). Filtered and federated searching is employed to facilitate focused searching so that learners can find the right resource with least effort and in minimum time. NDLI provides user group-specific services such as Examination Preparatory for School and College students and job aspirants. Services for Researchers and general learners are also provided. NDLI is designed to hold content of any language and provides interface support for 10 most widely used Indian languages. It is built to provide support for all academic levels including researchers and life-long learners, all disciplines, all popular forms of access devices and differently-abled learners. It is designed to enable people to learn and prepare from best practices from all over the world and to facilitate researchers to perform inter-linked exploration from multiple sources. It is developed, operated and maintained from Indian Institute of Technology Kharagpur.
Learn more about this project from here.
NDLI is a conglomeration of freely available or institutionally contributed or donated or publisher managed contents. Almost all these contents are hosted and accessed from respective sources. The responsibility for authenticity, relevance, completeness, accuracy, reliability and suitability of these contents rests with the respective organization and NDLI has no responsibility or liability for these. Every effort is made to keep the NDLI portal up and running smoothly unless there are some unavoidable technical issues.
Ministry of Education, through its National Mission on Education through Information and Communication Technology (NMEICT), has sponsored and funded the National Digital Library of India (NDLI) project.
| Sl. | Authority | Responsibilities | Communication Details |
|---|---|---|---|
| 1 | Ministry of Education (GoI), Department of Higher Education |
Sanctioning Authority | https://www.education.gov.in/ict-initiatives |
| 2 | Indian Institute of Technology Kharagpur | Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project | https://www.iitkgp.ac.in |
| 3 | National Digital Library of India Office, Indian Institute of Technology Kharagpur | The administrative and infrastructural headquarters of the project | Dr. B. Sutradhar bsutra@ndl.gov.in |
| 4 | Project PI / Joint PI | Principal Investigator and Joint Principal Investigators of the project |
Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon |
| 5 | Website/Portal (Helpdesk) | Queries regarding NDLI and its services | support@ndl.gov.in |
| 6 | Contents and Copyright Issues | Queries related to content curation and copyright issues | content@ndl.gov.in |
| 7 | National Digital Library of India Club (NDLI Club) | Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach | clubsupport@ndl.gov.in |
| 8 | Digital Preservation Centre (DPC) | Assistance with digitizing and archiving copyright-free printed books | dpc@ndl.gov.in |
| 9 | IDR Setup or Support | Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops | idr@ndl.gov.in |
|
Loading...
|