Membrane bound PCR

Re-usable DNA template for the polymerase chain reaction

DNA covalently bound to an uncharged nylon membrane was used for consecutive amplifications of several different genes by PCR. Successful PCR amplifications were obtained for membrane-bound genomic and plasmid DNA. Membrane-bound genomic DNA templates were re-used at least 15 times for PCR with specific amplification of the desired gene each time. PCR amplifications of specific sequences of p53, p16, CYP1A1, CYP2D6, GSTM1 and GSTM3 were performed independently on the same strips of uncharged nylon membrane containing genomic DNA. PCR products were subjected to restriction fragment length polymorphism analysis, single-strand conformational polymorphism analysis and/or dideoxy sequencing to confirm PCR-amplified gene sequences. We found that PCR fragments obtained by amplification from bound genomic DNA as template were identical in sequence to those of PCR products obtained from free genomic DNA in solution. PCR was performed using as little as 5 ng genomic or 4 fg plasmid DNA bound to membrane. These results suggest that DNA covalently bound to membrane can be re-used for sample-specific PCR amplifications, providing a potentially unlimited source of DNA for PCR.

Use of solid-phase PCR for enhanced detection of airborne microorganisms

The solid-phase PCR (SP-PCR) was compared with a culture-based technique for the detection of aerosolized Escherichia coli DH1. Results with SP-PCR showed an increase in detection sensitivity over that of culture methods. Therefore, SP-PCR may be useful for the detection of airborne microorganisms which may be nonculturable because of aerosolization or sampling stress.

PCR amplification of DNA sequences from nitrocellulose-bound, immunostained bacterial colonies

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Discrimination between alpha-satellite DNA sequences from chromosomes 21 and 13 by using polymerase chain reaction

alpha-Satellite subfamilies from chromosomes 21 and 13 are almost identical in sequence and cannot be distinguished from each other by hybridization techniques. A general method based on membrane-bound PCR is described here, allowing the discrimination of alpha-satellite DNA sequences from each of these two chromosomes, after detection by Southern blot hybridization. The PCR conditions were developed using somatic hybrid DNAs. The method was tested in membrane-bound PCR by using the alpha-satellite bands from a Southern blot of a CEPH family. The chromosomal origin of these bands, previously determined by linkage analysis, was confirmed by this method.

Amplification of nucleic acids by polymerase chain reaction (PCR) and other methods and their applications

The in vitro replication of DNA, principally using the polymerase chain reaction (PCR), permits the amplification of defined sequences of DNA. By exponentially amplifying a target sequence, PCR significantly enhances the probability of detecting target gene sequences in complex mixtures of DNA. It also facilitates the cloning and sequencing of genes. Amplification of DNA by PCR and other newly developed methods has been applied in many areas of biological research, including molecular biology, biotechnology, and medicine, permitting studies that were not possible before. Nucleic acid amplification has added a new and revolutionary dimension to molecular biology. This review examines PCR and other in vitro nucleic acid amplification methodologies--examining the critical parameters and variations and their widespread applications--giving the strengths and limitations of these methodologies.