http://dx.doi.org/10.46889/JCIM.2025.6107 https://athenaeumpub.com/journal-of-clinical-immunology-microbiology/ Research Article Applications of Spectrophotometric Methods and SDS-PAGE In Quantification of Total Soluble Proteins in Escherichia coli From Raw Meat, Offals and Rectal Swabs of Cattle in Gwagwalada Olabode Olatunde Kazeem 1 , Mailafia Samuel 1* , Ameh James Agbo 1 , Martha Echioda Ogbole 1 , Monday Onakpa 2 , Wesley Daniel Nafarnda 3 1 Faculty of Veterinary Medicine, Department of Veterinary Microbiology, University of Abuja, Nigeria 2 Faculty of Veterinary Medicine, Department of Pharmacology and Toxicology, Nigeria 3 Faculty of Veterinary Medicine, Department of Public Health and Preventive Medicine, Nigeria *Correspondence author: Mailafia Samuel, Faculty of Veterinary Medicine, Department of Veterinary Microbiology, University of Abuja, Nigeria; Email: smailafia@gmail.com Abstract The study was carried out to quantify the total soluble protein profile of nine Escherichia coli isolates from raw meat, offals and rectal swab by spectrotrophotmetric method. The results indicated that the virulent strains with highest concentration of protein from rectal swab was 19.19 µg followed by raw meat 15.88 µg while the lowest concentration of proteins from raw meat was 8.35 µg, lowest for offals was 10.55 µg and the lowest for rectal swab was 12.95 µg. this was followed by the electropherogram of the nine E. coli strains by Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis (SDS-PAGE). E. coli isolates from raw meat, offals and rectal swab when compared with the marker, were similar in their molecular weights. The obtained results displayed bands that are both faint and dense, appearing at different approximate molecular weights of 17 KDa, 34 KDa, 43 KDa, and 55 KDa. The results of our protein profiles showed a clear indication of the genetic relatedness between diver’s members of the Escherichia strains. It is an indication of their close genetic relatedness within the members of the Enterobacteriaceae species. E. coli organisms are therefore regarded as heterogenous groups of bacteria of pathogenic significance which are responsible for virulence and pathopgenicity. This information is novel as it could be used as a standard for further classification and understanding the diversity of the members of the genus Escherichia. Further studies including the analysis of the virulent genes cloning and expression of genes of interest is necessary to identify new strains of Escherichia coli. Keywords: Escherichia Coli; SDS-PAGE; Protein; Raw Meat; Offals; Rectal Swab and KDa Introduction E. coli are microbial pathogens that inhabit the Gastro Intestinal Tract (GIT) of both healthy animals and man [1]. E. coli in the genus Escherichia is a member of the family Enterobacteriaceae are facultative anaerobes, rod-shaped bacteria and has been identified as indicator species of fecal and enteric pathogen [2]. E. coli strains are not-pathogenic, some are known to cause significant human gastrointestinal disorders such as HC and HUS Shiga toxins (stx 1 and stx 2) Henterohaemolysin (lyA) and intimin (eaeA) are virulence factors that play a key role in the development of the disorders [3]. During various phases of growth, bacteria produce Membrane Vesicles (MVs) that contain much of the biological content derived from their parent bacterial cells, such as phospholipids, Lipopolysaccharides (LPS), proteins, enzymes, toxins, DNA and RNA [4]. Citation: Kazeem OO, et al. Applications of Spectrophotometric Methods and SDS-PAGE In Quantification of Total Soluble Proteins in Escherichia coli From Raw Meat, Offals and Rectal Swabs of Cattle in Gwagwalada. J Clin Immunol Microbiol. 2025;6(1):1-7. http://dx.doi.org/10.46889/JCIM.2025. 6107 Received Date: 08-04-2025 Accepted Date: 23-04-2025 Published Date: 29-04-2025 Copyright: © 2025 by the authors. Submitted for possible open access publication under the terms and conditions of the Creative Commons Attribution (CCBY) license (https://creativecommons.org/li censes/by/4.0/).