TY - JOUR
T1 - A novel locus of Yersinia enterocolitica serotype O:3 involved in lipopolysaccharide outer core biosynthesis
AU - Skurnik, Mikael
AU - Venho, Reija
AU - Toivanen, Paavo
AU - Al-Hendy, Ayman
PY - 1995/8
Y1 - 1995/8
N2 - Yersinia enterocolitica serotype O:3 strain 6471/76-c (Y-O3-c) was sensitive to bacteriophage ∅R1-37 when grown at 37°C but not when grown at 22°C because of steric hindrance by abundant lipopolysaccharide (LPS) O-side chain (O-antigen) expressed at 22°C. The transposon library of YeO3-c was grown at 37°C and screened for phage ∅R1-37-resistant transposon insertion mutants. Three types of mutant were isolated: (i) phage receptor mutants expressing O-antigen (LPS-smooth), (ii) phage receptor mutants not expressing O-antigen (LPS-rough), and (iii) LPS-smooth mutants with the phage receptor constitutively sterically blocked. Mutant type (i) was characterized in detail; the transposon insertion inactivates an operon, named the trs operon. The main findings based on this mutant are: (i) the trs operon is involved in the biosynthesis of the LPS outer core in YeO3-c; the nucleotide sequence of the trs operon revealed eight novel genes showing similarity to known polysaccharide biosynthetic genes of various Gram-negative bacteria as well as to capsule biosynthesis genes of Staphylococcus aureus; (ii) the biosynthesis of the core of YeO3-c involves at least two genetic loci; (iii) the trs operon is required for the biosynthesis of the bacteriophage ∅R1-37 receptor structures; (iv) the homopolymeric O-antigen of YeO8e is ligated to the inner core in Y. enterocolitica O:3; (v) the trs operon is located between the adk-hemH and galE-gsk gene pairs in the Y. enterocolitica chromosome; and (vi) the phage ∅R1-37 receptor is present in many but not in all Y. entesocolitica serotypes. The results also allow us to speculate that the trs operon is a relic of the ancestral rfb region of Y. enterocolitica O:3 carying genes indispensable for the completion of the core poplysaccharide biosynthesis.
AB - Yersinia enterocolitica serotype O:3 strain 6471/76-c (Y-O3-c) was sensitive to bacteriophage ∅R1-37 when grown at 37°C but not when grown at 22°C because of steric hindrance by abundant lipopolysaccharide (LPS) O-side chain (O-antigen) expressed at 22°C. The transposon library of YeO3-c was grown at 37°C and screened for phage ∅R1-37-resistant transposon insertion mutants. Three types of mutant were isolated: (i) phage receptor mutants expressing O-antigen (LPS-smooth), (ii) phage receptor mutants not expressing O-antigen (LPS-rough), and (iii) LPS-smooth mutants with the phage receptor constitutively sterically blocked. Mutant type (i) was characterized in detail; the transposon insertion inactivates an operon, named the trs operon. The main findings based on this mutant are: (i) the trs operon is involved in the biosynthesis of the LPS outer core in YeO3-c; the nucleotide sequence of the trs operon revealed eight novel genes showing similarity to known polysaccharide biosynthetic genes of various Gram-negative bacteria as well as to capsule biosynthesis genes of Staphylococcus aureus; (ii) the biosynthesis of the core of YeO3-c involves at least two genetic loci; (iii) the trs operon is required for the biosynthesis of the bacteriophage ∅R1-37 receptor structures; (iv) the homopolymeric O-antigen of YeO8e is ligated to the inner core in Y. enterocolitica O:3; (v) the trs operon is located between the adk-hemH and galE-gsk gene pairs in the Y. enterocolitica chromosome; and (vi) the phage ∅R1-37 receptor is present in many but not in all Y. entesocolitica serotypes. The results also allow us to speculate that the trs operon is a relic of the ancestral rfb region of Y. enterocolitica O:3 carying genes indispensable for the completion of the core poplysaccharide biosynthesis.
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U2 - 10.1111/j.1365-2958.1995.mmi_17030575.x
DO - 10.1111/j.1365-2958.1995.mmi_17030575.x
M3 - Article
C2 - 8559076
AN - SCOPUS:0029096439
SN - 0950-382X
VL - 17
SP - 575
EP - 594
JO - Molecular Microbiology
JF - Molecular Microbiology
IS - 3
ER -