Question

discuss current techniques used to determine microbial taxonomy and phylogeny. In your answer, describe in detail the use of molecular techniques including computer software that are used in phylogenetics

Answer 1

Tecnique for determining microbial taxonomy and phylogeny

CLASSICAL CHARACTERISTIC

• morphological
• physiological
• metabolic
• ecological
• genetic

MOLECULAR CHARACTERISTIC

• nucleic acid base composition

NUCLEIC ACID HYBRIDISATION

• nucleic acid sequencing

GENOMIC FINGERPRINTING

• aminoacid sequencing

ECOLOGICAL CHARACTERISTIC

• life cycle pattern
• symbiotic relationship
• ability to cause disease
• habitat preference
• growth requirement

GENETIC ANALYSIS

• transformation
• conjugation
• plasmid content

microbial phylogeny are assess by using various method

1. molecular chronometer: changesin the conversed protein or gene without destroying or altering the molecular function.
2. phylogenetic trees: the organisms generated like a tree that express the difference as an evolutionary distance
3. signature sequence: particualar group pf microbes will possess unique nucleotide at specific location in 16s rRNA molecule.
4. polyphasic taxonomy: taxomic scheme which consider the wide range of stable and accepted and genotypic information.

USING OF MOLECULAR TECHNIQUE INCLUDE COMPUTER SOFTWARE USED IN PHYLOGENETICS

MEGA (molecular evolutionary genetics analysis) is analysis software that is userfriendly and free to download and use.

popular phylogeny programs using statistical approach such as fastDNAml(26), MrBayes(15), TREE-PUZZLE(41).