Yu-Chieh Liao

MyPro: A seamless pipeline for automated prokaryotic genome assembly and annotation

MyPro is a software pipeline for high-quality prokaryotic genome assembly and annotation. It was validated on 18 oral streptococcal strains to produce submission-ready, annotated draft genomes. MyPro installed as a virtual machine and supported by updated databases will enable biologists to perform quality prokaryotic genome assembly and annotation with ease.

Draft Genome Sequences of 18 Oral Streptococcus Strains That Encode Amylase-Binding Proteins

ABSTRACT A number of commensal oral streptococcal species produce a heterogeneous group of proteins that mediate binding of salivary α-amylase. This interaction likely influences streptococcal colonization of the oral cavity. Here, we present draft genome sequences of several strains of oral streptococcal species that bind human salivary amylase.

Draft Genome Sequence of the Mycobacterium tuberculosis Clinical Isolate C2, Belonging to the Latin American-Mediterranean Family.

ABSTRACT Tuberculosis remains a major infectious disease in Taiwan. Here we present the draft genome sequence of the Mycobacterium tuberculosis C2 strain, belonging to the Latin American–Mediterranean lineage. The draft genome sequence comprises 4,453,307 bp with a G+C content of 65.6%, revealing 4,390 coding genes and 45 tRNA genes.

Draft Genome Sequences of the Mycobacterium tuberculosis Clinical Strains A2 and A4, Isolated from a Relapse Patient in Taiwan.

ABSTRACT The recurrence rate of Mycobacterium tuberculosis in Taiwan is 3%. Here, we present the draft genome sequences of M. tuberculosis strains A2 and A4 from a relapse patient. The draft genome sequences comprise 4,443,031 bp and 4,487,096 bp, revealing 4,220 and 4,143 coding sequences for A2 and A4, respectively, as well as 49 tRNA genes for the both isolates.

Monitoring the antigenic evolution of human influenza A viruses to understand how and when viruses escape from existing immunity

BackgroundThe World Health Organization (WHO) organizes consultations in February and September of each year, spearheaded by an advisory group of experts to analyze influenza surveillance data generated by the WHO Global Influenza Surveillance and Response System (GISRS). The purpose of these consultations is to recommend the composition on influenza virus vaccines for the northern and southern hemispheres, respectively. The latest news of influenza viruses is made available to the public and updated on the WHO website. Although WHO discloses the manner in which it has made the recommendation, usually by considering epidemiological and clinical information to analyze the antigenic and genetic characteristics of seasonal influenza viruses, most individuals do not possess an understanding of antigenic drift and when it occurs.FindingsWe have constructed a web server, named Fluctrl, and implemented a pipeline whereby HA sequence data is downloaded from the Influenza Virus Resource at NCBI along with their isolation information including isolation year and location, which are parsed and managed in MySQL database. By analyzing the frequency of each amino acid residue of the HA1 domain expressed by the viruses on annual basis, users are able to obtain evolutionary dynamics of human influenza viruses corresponding with epidemics. Users are able to upload and analyze their HA1 sequences for generating evolutionary dynamics. In addition, a distribution of amino acid residues at a particular site is represented geographically to trace the location where antigenic variants are seeded.ConclusionsFluctrl is constructed for monitoring the antigenic evolution of human influenza A viruses. This tool is intended to inform the general public how and when influenza viruses evade the human bodys immunity. Furthermore, leveraging the geographic information, the original locations of emerging influenza viruses can be traced. Fluctrl is freely accessible at http://sb.nhri.org.tw/fluctrl.

Simultaneous detections of genetic fragment and single nucleotide mutation with a three-tiered output for tuberculosis diagnosis

Tuberculosis (TB) remains one of the major infectious diseases worldwide. The pathogenic bacterium, Mycobacterium tuberculosis (M.tb), continuously evolves strains carrying drug-resistance genes, thus posing a growing challenge to TB prevention and treatment. We report a diagnostic system that uses a molecular beacon probe and an assistant strand as the core to simultaneously interact with an M.tb-specific fragment (in IS6110) and a single nucleotide substitution (SNS)-encoded segment (in rpoB) associated with drug resistance. A single fluorescent output in three-tiered levels was produced for combinatorial interpretations based on formation of a four-way DNA junction (4WJ). The SNS caused the 4WJ to partially dissociate, thus resulting in medium-level fluorescence. By contrast, high- and low-level fluorescence, represented the complete complementary complex and absence of either targeted fragments, respectively. Manipulating the length of the analyte-binding arm realized the medium output. The thermodynamics and kinetics of 4WJ construction were investigated to maximize the tiered-output performance. Biocatalytic amplification driven by the Klenow Fragment and Nt.AlwI was incorporated into the method to enhance the signal 64-fold and ensure long-term stability of the three-tiered output. The detection accuracy of the sensing system was verified using unpurified amplicons with templates of extracted DNA and boiled bacterial solutions. The tiered-output mechanism was usable at bacterial loads ranging from 4 × 100 to 4 × 103 CFU per reaction. The interference caused by nontuberculous mycobacteria was minimal. The results demonstrated the integrity of the sensing method as an alternative strategy for rapid screening of M.tb and detecting rifampin-resistance.

Veillonella infantium sp. nov., an anaerobic, Gram-stain-negative coccus isolated from tongue biofilm of a Thai child

A strain of a novel anaerobic, Gram-stain-negative coccus was isolated from the tongue biofilm of a Thai child. This strain was shown, at the phenotypic level and based on 16S rRNA gene sequencing, to be a member of the genus Veillonella. Comparative analysis of the 16S rRNA, dnaK and rpoB gene sequences indicated that phylogenetically the strain comprised a distinct novel branch within the genus Veillonella. The novel strain showed 99.8, 95.1 and 95.9 % similarity to partial 16S rRNA, dnaK and rpoB gene sequences, respectively, to the type strains of the two most closely related species, Veillonelladispar ATCC 17748T and Veillonellatobetsuensis ATCC BAA-2400T. The novel strain could be discriminated from previously reported species of the genus Veillonella based on partial dnaK and rpoB gene sequencing and average nucleotide identity values. The major acid end-product produced by this strain was acetic acid under anaerobic conditions in trypticase-yeast extract-haemin with 1 % (w/v) glucose or fructose medium. Lactate was fermented to acetic acid and propionic acid. Based on these observations, this strain represents a novel species, for which the name Veillonella infantium sp. nov. is proposed. The type strain is T11011-4T (=JCM 31738T=TSD-88T).