Complete sequence of the cap locus of Haemophilus influenzae serotype b and nonencapsulated b capsule-negative variants.
نویسندگان
چکیده
The complete capsule (cap) loci from three Haemophilus influenzae strains, one serotype b (Hib) and two nonencapsulated b capsule-negative variants, were sequenced. Two new open reading frames, hcsA and hcsB, were identified in region III and thought to be involved in postpolymerization modification of the capsule. The location of the cap locus in the Haemophilus influenzae chromosome was identified within section 97 of the Rd genome (chromosomal coordinates 1074542 to 1086327) and found to be the same for the Hib and two Hib(-) strains as well as some other encapsulated division I H. influenzae strains.
منابع مشابه
Genetic analysis of the capsule locus of Haemophilus influenzae serotype f.
A 19-kb DNA region containing genes involved in the biosynthesis of the capsule of Haemophilus influenzae serotype f (Hif) has been cloned and characterized. The Hif cap locus organization is typical of group II capsule biosynthetic loci found in other H. influenzae serotype b bacteria and other gram-negative bacteria. However, the Hif cap locus was not associated with an IS1016 element. Three ...
متن کاملCapsulation loci of non-serotype b encapsulated Haemophilus influenzae.
Invasive infections caused by non-type b encapsulated Haemophilus influenzae have increased recently. Because capsule is a major virulence factor, capsulation of 62 recently isolated non-serotype b encapsulated strains was examined. Repeated serotyping confirmed only 69.0% of isolates. The combination of slide agglutination and cap genotyping confirmed 78.9% of type a, 100% of type e, and 86.4%...
متن کاملA study on Haemophilus influenzae type b growth rate and capsule production in different media
In the present study, seven isolates of Haemophilus influenzae type b were cultured in four different media to compare growth rate and capsule production. Four liquid media namely brain heart infusion broth (BHI), trypticase soy broth (TSB), Mueller Hinton Broth (MHB) and Gonococci broth (GC) with added supplements (1% hemoglobin, 1% Isovitalex) were used. The growth was measured by colony coun...
متن کاملGenetic characterization of the capsulation locus of Haemophilus influenzae serotype e.
The capsulation (cap) locus of Haemophilus influenzae type e (Hie) was characterized and sequenced. No IS1016 element was found to flank the locus. The 18.2-kb locus included 14 open reading frames (ORFs), which were grouped into three functional regions. Eight new ORFs (named ecs1 to ecs8) were identified in the Hie capsule-specific region II.
متن کاملGenes involved in Haemophilus influenzae type b capsule expression are part of an 18-kilobase tandem duplication.
Encapsulated Haemophilus influenzae type b produce nonencapsulated variants at high frequency (0.1-0.3%). Cosmid cloning was used to investigate the genetic mechanism responsible for this instability. Analysis of three independently derived cosmid clones showed that the b+ parental strain contains an 18-kilobase tandem duplication of genes involved in type b capsule expression. Loss of one comp...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Infection and immunity
دوره 71 6 شماره
صفحات -
تاریخ انتشار 2003