PMID-sentid Pub_year Sent_text comp_official_name comp_offsetprotein_name organism prot_offset 15470099-4 2004 In chs3 mutants, which lack the chitosan and dityrosine layers of the spore wall, bridges are absent. dityrosine 45-55 chitin synthase CHS3 Saccharomyces cerevisiae S288C 3-7