The genome of Salmonella typhi CT18 was sequenced to understand its genetic basis for host restriction and potential eradication. The genome was assembled from 97,000 end sequences with 7.9× coverage, supplemented by 0.7× coverage from M13mp18 libraries. The sequence was annotated using a gene-finding tool trained for S. typhi and compared with S. typhimurium to identify deletions and insertions. Pseudogenes were identified by comparing with S. typhimurium and verified against original sequencing data. The genome sequence was submitted to EMBL with accession numbers AL513382 (chromosome), AL513383 (pHCM1), and AL513384 (pHCM2). The complete genome sequence of Salmonella enterica serovar Typhimurium LT2 was determined, revealing a 4,857-kilobase chromosome and a 94-kilobase virulence plasmid. The genome was compared with eight related enterobacterial genomes, showing that 11% of S. typhimurium LT2 genes are missing in S. typhi and 29% in E. coli K12. The 352 gene homologues confined to subspecies I of S. enterica are useful for studying epidemiology, host specificity, and pathogenesis. The genome contains 4,330 open reading frames (ORFs) and 12 putative operons of the chaperone–usher assembly class. The genome also includes four functional prophages and a plasmid pSLT. The S. typhimurium LT2 genome was compared with other enterobacterial genomes, revealing that most genes are collinear except for inversions near the replication terminus. The genome contains a large duplicated region of coding sequences (CDS) and several pathogenicity islands (SPIs). The genome also includes genes for fimbriae and potential virulence factors. The genome has a high number of pseudogenes, which may contribute to the host restriction of S. typhi. The genome was annotated using Acedb, GeneMark, and Glimmer, and compared with the S. typhi annotation. The study highlights the importance of understanding the genetic basis of host adaptation and pathogenicity in Salmonella. The genome sequence provides insights into the evolution and function of Salmonella, and may aid in the development of vaccines and therapies. The study also emphasizes the role of lateral gene transfer in the evolution of Salmonella and the importance of genomic comparisons in understanding bacterial diversity and pathogenesis.The genome of Salmonella typhi CT18 was sequenced to understand its genetic basis for host restriction and potential eradication. The genome was assembled from 97,000 end sequences with 7.9× coverage, supplemented by 0.7× coverage from M13mp18 libraries. The sequence was annotated using a gene-finding tool trained for S. typhi and compared with S. typhimurium to identify deletions and insertions. Pseudogenes were identified by comparing with S. typhimurium and verified against original sequencing data. The genome sequence was submitted to EMBL with accession numbers AL513382 (chromosome), AL513383 (pHCM1), and AL513384 (pHCM2). The complete genome sequence of Salmonella enterica serovar Typhimurium LT2 was determined, revealing a 4,857-kilobase chromosome and a 94-kilobase virulence plasmid. The genome was compared with eight related enterobacterial genomes, showing that 11% of S. typhimurium LT2 genes are missing in S. typhi and 29% in E. coli K12. The 352 gene homologues confined to subspecies I of S. enterica are useful for studying epidemiology, host specificity, and pathogenesis. The genome contains 4,330 open reading frames (ORFs) and 12 putative operons of the chaperone–usher assembly class. The genome also includes four functional prophages and a plasmid pSLT. The S. typhimurium LT2 genome was compared with other enterobacterial genomes, revealing that most genes are collinear except for inversions near the replication terminus. The genome contains a large duplicated region of coding sequences (CDS) and several pathogenicity islands (SPIs). The genome also includes genes for fimbriae and potential virulence factors. The genome has a high number of pseudogenes, which may contribute to the host restriction of S. typhi. The genome was annotated using Acedb, GeneMark, and Glimmer, and compared with the S. typhi annotation. The study highlights the importance of understanding the genetic basis of host adaptation and pathogenicity in Salmonella. The genome sequence provides insights into the evolution and function of Salmonella, and may aid in the development of vaccines and therapies. The study also emphasizes the role of lateral gene transfer in the evolution of Salmonella and the importance of genomic comparisons in understanding bacterial diversity and pathogenesis.