Although the applicability of small subunit ribosomal RNA (16S rRNA) sequences for bacterial classification is now well accepted, the general use of these molecules has been hindered by the technical difficulty of obtaining their sequences. A protocol is described for rapidly generating large blocks of 16S rRNA sequence data without isolation of the 16S rRNA or cloning of its gene. The 16S rRNA...

Concerns about the deleterious effects of missing data may often determine which characters and taxa are included in phylogenetic analyses. For example, researchers may exclude taxa lacking data for some genes or exclude a gene lacking data in some taxa. Yet, there may be very little evidence to support these decisions. In this paper, I review the effects of missing data on phylogenetic analyse...

DNA sequences and other molecular data compared among organisms may contain phylogenetic signal, or they may be randomized with respect to phylogenetic history. Some method is needed to distinguish phylogenetic signal from random noise to avoid analysis of data that have been randomized with respect to the historical relationships of the taxa being compared. We analyzed 8,000 random data matric...

Phylogenetic analyses of 110 serpin protein sequences revealed clades consistent with independent phylogenetic analyses based on exon-intron structure and diagnostic amino acid sites. Trees were estimated by maximum likelihood, neighbor joining, and partial split decomposition using both the BLOSUM 62 and Jones-Taylor-Thornton substitution matrices. Neighbor-joining trees gave results closest t...

infectious bursal disease (ibd) is a highly contagious disease of chickens caused by the infectious bursal disease virus (ibdv). this study was conducted to characterize three ibdv strains from iran. a reverse transcriptase-polymerase chain reaction (rt-pcr) procedure was used to amplify a 715-bp fragment of the vp1 gene from ibdv strains. amplified vp1 fragments of the three iranian ibdv strai...

This study represents phylogenetic analyses of two woody polygonaceous genera Calligonum and Pteropyrum using both chloroplast fragment (trnL-F) and the nuclear ribosomal internal transcribed spacer (nrDNA ITS) sequence data. All inferred phylogenies using parsimony and Bayesian methods showed that Calligonum and Pteropyrum are both monophyletic and closely related taxa. They have no affinity w...