Carol Huang

University of California, Davis | UCD · Department of Population Health and Reproduction (VM)

Food-producing animals such as dairy cattle are potential reservoirs of antimicrobial resistance (AMR), with multidrug-resistant (MDR) organisms such as Escherichia coli observed in higher frequency in young calves compared to older cattle. In this study, we characterized the genomes of enteric MDR E. coli from pre-weaned dairy calves with and with...

The rising prevalence of extended-spectrum β-lactamase (ESBL)-producing Enterobacterales is a significant threat to animal and human health. This study aims to describe the clinical features, antimicrobial susceptibility patterns, and genotypic features of infections associated with ESBL-producing Enterobacterales in dogs and cats seen at a tertiar...

Rodents and bats are the most diverse mammal group that host Bartonella species. In the Americas, they were described as harboring Bartonella species; however, they were mostly characterized to the genotypic level. We describe here Bartonella isolates obtained from blood samples of one rodent (Peromyscus yucatanicus from San José Pibtuch, Yucatan)...

Malnourishment is a risk factor for childhood mortality, jeopardizing the health of children by aggravating pneumonia/acute respiratory infections and diarrheal diseases. Malnourishment causes morphophysiological changes resulting in stunting and wasting that have long-lasting consequences such as cognitive deficit and metabolic dysfunction. Using...

In this work, we hypothesized that shifts in the food microbiome can be used as an indicator of unexpected contaminants or environmental changes. To test this hypothesis, we sequenced the total RNA of 31 high protein powder (HPP) samples of poultry meal pet food ingredients. We developed a microbiome analysis pipeline employing a key eukaryotic mat...

Hungatella hathewayi has been observed to be a member of the gut microbiome. Unfortunately, little is known about this organism in spite of being associated with human fatalities; it is important to understand virulence mechanisms and epidemiological prospective to cause disease. In this study, a patient with chronic neurologic symptoms presented t...

Vibrio parahaemolyticus is the most common cause of seafood-borne illness reported in the United States. Draft genomes of 132 North American clinical and oyster V. parahaemolyticus isolates were sequenced to investigate their phylogenetic and biogeographic relationships. The majority of oyster isolate sequence types (STs) were from a single harvest...

Sierra Mixe maize is a landrace variety from Oaxaca, Mexico, that utilizes nitrogen derived from the atmosphere via an undefined nitrogen fixation mechanism. The diazotrophic microbiota associated with the plant's mucilaginous aerial root exudate composed of complex carbohydrates was previously identified and characterized by our group where we fou...

A geographically isolated maize landrace cultivated on nitrogen-depleted fields without synthetic fertilizer in the Sierra Mixe region of Oaxaca, Mexico utilizes nitrogen derived from the atmosphere and develops an extensive network of mucilage-secreting aerial roots that harbors a diazotrophic (N2-fixing) microbiota. Targeting these diazotrophs, w...

In this work, we hypothesized that shifts in the food microbiome can be used as an indicator of unexpected contaminants or environmental changes. To test this hypothesis, we sequenced total RNA of 31 high protein powder (HPP) samples of poultry meal pet food ingredients. We developed a microbiome analysis pipeline employing a key eukaryotic matrix...

Here we propose that using shotgun sequencing to examine food leads to accurate authentication of ingredients and detection of contaminants. To demonstrate this, we developed a bioinformatic pipeline, FASER (Food Authentication from SEquencing Reads), designed to resolve the relative composition of mixtures of eukaryotic species using RNA or DNA se...

Traditional taxonomy in biology assumes that life is organized in a simple tree. Attempts to classify microorganisms in this way in the genomics era led microbiologists to look for finite sets of 'core' genes that uniquely group taxa as clades in the tree. However, the diversity revealed by large-scale whole genome sequencing is calling into questi...

Non-jejuni Campylobacter species identification is quite challenging for a diagnostic microbiology laboratory due to suboptimal isolation protocols and lack of differentiating biochemical features. Here we applied whole genome sequencing in an outbreak investigation of a cryptic pathogen Campylobacter hyointestinalis subsp. hyointestinalis in great...

The goal of the project is to determine novel biomarkers of abortion in ruminants due to Campylobacter jejuni infection using predictive modeling of whole genome sequencing and machine learning. Determining the genomic basis for phenotypes is going to impact infectious disease surveillance, vaccine design and public health. Here we applied a novel...

Taxonomic classification is an essential step in the analysis of microbiome data that depends on a reference database of whole genome sequences. Taxonomic classifiers are built on established reference species, such as the Human Microbiome Project database, that is growing rapidly. While constructing a population wide pangenome of the bacterium Hun...

Bacillus velezensis CE2 produces potent antimicrobial compound(s). The draft genome sequence of the strain reported here is 4.1 Mb with a G+C content of 46.1%. Whole-genome sequencing revealed that the strain genetically encodes a novel multicomponent lantibiotic, velezensicidin.

Figure 1: 100K Pathogen Genome Project sample preparation workflow for multiplexed, short-read Illumina sequencing Figure 3: Detailed KAPA HTP Library Preparation protocol. The input into library construction is fragmented DNA or cDNA. Each enzymatic reaction is followed by a SPRI-bead cleanup. The "with-bead" protocol uses a single aliquot of SPRI...

Chitinases are glycosyl hydrolases that catalyze the hydrolysis of the β-1,4 linkages in complex carbohydrates and those that contain GlcNAc. These enzymes are considered emerging virulence factors during infection because the host glycan changes. This is the release of four single chitinase deletion mutants in Salmonella enterica serovar Typhimuri...

Salmonella is a common food-associated bacterium that has substantial impact on worldwide human health and the global economy. This is the public release of 1,183 Salmonella draft genome sequences as part of the 100K Pathogen Genome Project. These isolates represent global genomic diversity in the Salmonella genus.

Lysozyme enzymes hydrolyze the β-1,4-glycosidic bond in oligosaccharides. These enzymes are part of a broad group of glucoside hydrolases that are poorly characterized; however, they are important for growth and are being recognized as emerging virulence factors. This is the release of four lysozyme-encoding-gene-deletion mutants in Salmonella ente...

The Salmonella Syst-OMICS consortium is sequencing 4,500 Salmonella genomes and building an analysis pipeline for the study of Salmonella genome evolution, antibiotic resistance and virulence genes. Metadata, including phenotypic as well as genomic data, for isolates of the collection are provided through the Salmonella Foodborne Syst-OMICS databas...

Amylases catalyze the cleavage of α- d -1,4 and α- d -1,6-glycosidic bonds in starch and related carbohydrates. Amylases are widely distributed in nature and are important in carbohydrate metabolism. This is the release of four single and two double deletions in Salmonella enterica serovar Typhimurium LT2 that are important for glycan degradation d...

Sialidases, which are widely distributed in nature, cleave the α-ketosidic bond of terminal sialic acid residue. These emerging virulence factors degrade the host glycan. We report here the release of seven sialidase and one sialic acid transporter deletion in Salmonella enterica serovar Typhimurium strain LT2, which are important in cellular invas...

Next Generation Sequencing (NGS) is a process that can be used to construct DNAlibraries for large-scale sequencing projects. NGS utilizes the input of high molecular weight and intact genomicDNA(gDNA) to construct high-quality libraries. The assessment ofDNAintegrity is a key step in library construction. The Agilent 2200 TapeStation System with t...

Shigella is a major foodborne pathogen that infects humans and non-human primates and is the major cause of dysentery and reactive arthritis worldwide. This is the initial public release of 16 Shigella genome sequences from four species sequenced as part of the 100K Pathogen Genome Project.

Campylobacter jejuni is an enteric bacterium that can cause abortion in livestock. This is the release of a multidrug-resistant Campylobacter jejuni genome from an isolate that caused an abortion in a cow in northern California. This isolate is part of the 100K Pathogen Genome Project.

The diversity revealed by large scale genomics in microbiology is calling into question long held beliefs about genome stability, evolutionary rate, even the definition of a species. MacArthur and Wilson's theory of insular biogeography provides an explanation for the diversity of macroscopic animal and plant species as a consequence of the associa...

The placenta is a functionally complex temporary organ of fetal origin, which among many roles serves as an immunological barrier, protecting the developing fetus from the maternal immune system. Due to its central role in fetal development and maintenance of pregnancy, placental pathology is implicated in several disorders and long-term health eff...

Many bacterial genomes are highly variable but nonetheless are typically published as a single assembled genome. Experiments tracking bacterial genome evolution have not looked at the variation present at a given point in time. Here, we analyzed the mouse-passaged Helicobacter pylori strain SS1 and its parent PMSS1 to assess intra-and intergenomic...

Many bacterial genomes are highly variable but nonetheless are typically published as a single assembled genome. Experiments tracking bacterial genome evolution have not looked at the variation present at a given point in time. Here, we analyzed the mouse-passaged Helicobacter pylori strain SS1 and its parent PMSS1 to assess intra- and intergenomic...

Campylobacter is a food-associated bacterium and a leading cause of foodborne illness worldwide, being associated with poultry in the food supply. This is the initial public release of 202 Campylobacter genome sequences as part of the 100K Pathogen Genome Project. These isolates represent global genomic diversity in the Campylobacter genus.

Campylobacter jejuni is an intestinal bacterium that can cause abortion in livestock. This publication announces the public release of 15 Campylobacter jejuni genome sequences from isolates linked to abortion in livestock. These isolates are part of the 100K Pathogen Genome Project and are from clinical cases at the University of California (UC) Da...

Importance: This study examined the link between public health and genomic variation of Campylobacter in relation to disease in humans, primates, and livestock. Use of large-scale whole genome sequencing enabled population level assessment to find new genes that are linked to livestock disease. With 184 Campylobacter genomes we assessed virulence...

BACKGROUND: Helicobacter pylori, a gram-negative bacterium associated with a spectrum of benign and malignant gastric conditions, is one of the most genetically variable pathogens. Its genome encodes a large number of DNA methyltransferases targeting specific motif sequences of ∼4-15 bp. DNA base modifications epigenetically regulate gene expressio...

Complex glycans cover the gut epithelial surface to protect the cell from the environment. Invasive pathogens must breach the glycan layer before initiating infection. While glycan degradation is crucial for infection, this process is inadequately understood. Salmonella contains 47 glycosyl hydrolases (GHs) that may degrade the glycan. We hypothesi...

The host gut epithelial membrane is shielded by complex glycans to protect the cell. Gastroenteritis begins when invasive pathogens bind and degrade the glycans at the epithelial barrier to gain access of host membrane. While glycan degradation is crucial for infection, this process is poorly understood. We hypothesized that Salmonella deploys its...

Next-generation whole genome sequencing of microbes demands rapid, robust, and scalable library construction workflows, capable of generating high-quality sequence data across a wide range of genome sizes, complexities and genomic GC content. In this Application Note, we describe a streamlined library preparation method that results in minimal bias...

A new method was developed to automate the KAPA HTP Library Preparation kit for microbial whole genome sequencing. This method uses the Agilent NGS Workstation, consisting of the NGS Bravo liquid handling platform with its accessories for heating, cooling, shaking, and magnetic bead manipulations in a 96-well format. User intervention in multistep...

Shearing of bacterial gDNA within a specific size range prior to sequencing library construction is a critical step in Next Generation Sequencing workflows. The quality control of the sheared bacterial gDNA is required in large multiplexed formats for large volume workflows, such as those used in the 100K Pathogen Genome Sequencing Project. Using t...

Next Generation Sequencing requires the input of high molecular weight genomic DNA to construct quality libraries for whole genome bacterial sequencing. Large scale sequencing projects, such as the 100K Pathogen Genome Project, require methods to rapidly assess the quantity and quality of the input DNA using high-throughput methods that are fast an...