C. Andrew Carson

Identification of Fecal Escherichia coli from Humans and Animals by Ribotyping

ABSTRACT Fecal pollution of water resources is an environmental problem of increasing importance. Identification of individual host sources of fecal Escherichia coli, such as humans, pets, production animals, and wild animals, is prerequisite to formulation of remediation plans. Ribotyping has been used to distinguish fecalE. coli of human origin from pooled fecal E. coli isolates of nonhuman origin. We have extended application of this technique to distinguishing fecal E. coli ribotype patterns from human and seven individual nonhuman hosts. Classification accuracy was best when the analysis was limited to three host sources. Application of this technique to identification of host sources of fecal coliforms in water could assist in formulation of pollution reduction plans.

Comparison of Ribotyping and Repetitive Extragenic Palindromic-PCR for Identification of Fecal Escherichia coli from Humans and Animals

ABSTRACT This report compares the performances of two popular genotypic methods used for tracking the sources of fecal pollution in water, ribotyping and repetitive extragenic palindromic-PCR (rep-PCR). The rep-PCR was more accurate, reproducible, and efficient in associating DNA fingerprints of fecal Escherichia coli with human and animal hosts of origin.

Use of a Bacteroides thetaiotaomicron‐specific α‐1‐6, mannanase quantitative PCR to detect human faecal pollution in water

Aims:  The aims of this work were to develop a quantitative test, based on Bacteroides thetaiotaomicron, for human faecal pollution in water and to evaluate test performance.

Development of Faecalibacterium 16S rRNA gene marker for identification of human faeces

Aims:  The focus of this study was to identify a bacterial 16S rRNA gene sequence, unique to microbiota in the human gut, for use in development of a dependable PCR assay to detect human faecal pollution in water.

Cloned lines of Babesia bovis differ in their ability to induce cerebral babesiosis in cattle.

Abstract Clones of a Babesia bovis isolate known to cause particularly severe cerebral babesiosis were tested for virulence phenotype by inoculation of cattle. Clones were selected for phenotyping by two criteria – rate of growth in culture and hybridization of a virulence-related probe to Southern blots. Largely on the basis of associated mortality, B. bovis clones were judged to vary in their pathogenic potential.

Use of random amplified polymorphic DNA analysis to compareBabesia bovis andB. bigemina isolates

Random amplified polymorphic DNA analysis provides characteristic fingerprints forBabesia bovis andB. bigemina. This genetic profile reflects similarities and minor differences between closely related regional isolates and the greater diversity representative of species from distant geographic locations.

Pulsed-Field Gel Elec rophoresis Pa ern Recogni ion of Bac erial DNA: A Systemic Approach

Abstract: Pulsed-Field Gel Electrophoresis (PFGE) images contain ‘banding pattern’ information that can be used in bacterial identification.A systemic approach was designed to target the bacterial DNA PFGE pattern recognition problem that requires image processing, feature extraction, data pre-processing, classification and final decision-making. This paper describes the research, development and testing of a complete system to address this identification problem, including Receiver Operating Characteristic Curve (ROC) analysis. Variations due to gel preparation in various laboratories by different technicians are considered. The approach was applied to recognition of E. coli O157:H7 bacteria with excellent results.

Fluorescence-activated cell sorting-derived clones ofBabesia bigemina show karyotype polymorphism

Use of the fluorescence-activated cell sorter proved to be an accurate and highly efficient means for cloningBabesia parasites. These qualities were examined by separating a mixed population ofBabesia-infected bovine erythrocytes composed of two isolates with different karyotypes. Direct evidence of polymorphism was detected during comparison of the resultant clones.