Pathogens Sequenciating

Sequenciaton

Pathogens Sequenciating

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DNA sequencing enables us to perform a thorough analysis of DNA because it provides us with the most basic information of all: the the sequence of nucleotides. With this knowledge, for example, we can locate regulatory and gene sequences, make comparisons between homologous genes across across species and identify mutations.

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Two methods were independently developed: chemical Enzimatic (Sanger’ (Sanger’s method). Sanger’ Sanger’s method became the standard

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B.K.Kolita Kamal Jinadasa, Jinadasa, Post Harvest Technology Division, NARA, ColomboColombo-15, Sri Lanka.

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Sanger’ Sanger’s method, is based on the use of dideoxynucleotides (ddNTP’ ddNTP’s) in addition to the normal nucleotides (NTP’ NTP’s) found in DNA. Dideoxynucleotides are essentially the same as nucleotides except they contain a hydrogen group on the 3’ carbon instead of a hydroxyl group (OH). These modified nucleotides, when integrated into a sequence, prevent the addition of further nucleotides..This occurs because a phosphodiester bond cannot form between the dideoxynucleotide and the next incoming nucleotide, and thus the DNA chain is terminated.

because of its practicality

Sequenciation results

Blast „

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In bioinformatics, bioinformatics, Basic Local Alignment Search Tool, or BLAST, BLAST, is an algorithm for comparing primary biological sequence information, such as the aminoamino-acid sequences of different proteins or the nucleotides of DNA sequences. sequences. A BLAST search enables a researcher to compare a query sequence with a library or database of sequences, and identify library sequences that resemble the query sequence above a certain threshold. To run, BLAST requires two sequences as input: a query sequence and a sequence database. BLAST searches for high scoring sequence alignments between the query sequence and sequences in the database using a heuristic approach approach that approximates the SmithSmith-Waterman algorithm

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Blast results Query sequence input

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Taxonomy tree

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