title: CS21 positive multidrug-resistant ETEC clinical isolates from children with diarrhea are associated with self-aggregation, and adherence.
abstract: BACKGROUND
  Enterotoxigenic Escherichia coli (ETEC) colonize the human intestinal mucosa using pili and non-pili colonization factors (CFs). CS21 (also designated Longus) is one of the most prevalent CFs encoded by a 14 kb lng DNA cluster located in a virulence plasmid of ETEC; yet limited information is available on the prevalence of CS21 positive ETEC isolates in different countries. The aim of this study was to evaluate the prevalence of CS21 among ETEC clinical isolates from Mexican and Bangladeshi children under 5 years old with diarrhea and to determine the phenotypic and genotypic features of these isolates.
  
  
  METHODS
  ETEC clinical isolates positive to lngA gene were characterized by genotype, multidrug-resistance, self-aggregation, biofilm formation, and adherence to HT-29 cell line.
  
  
  RESULTS
  A collection of 303 E. coli clinical isolates were analyzed, the 81.51% (247/303) were identified as ETEC, 30.76% (76/247) were st (+)/lt (+), and 25.10% (62/247) were positive for the lngA gene. Among the lngA (+) ETECs identified, 50% of isolates (31/62) were positive for LngA protein. The most frequent serotype was O128ac:H12 found in 19.35% (12/62) of lngA (+) ETEC studied. Multidrug-resistance (MDR) lngA (+) ETEC isolates was identified in 65% (39/60), self-aggregation in 48.38% (30/62), and biofilm formation in 83.87% (52/62). ETEC lngA (+) isolates were able to adhere to HT-29 cells at different levels. Two lngA isogenic mutants were constructed in the ETEC E9034A and ETEC73332 clinical isolate, showing a 77% and 98% reduction in adherence, respectively with respect to the wild type.
  
  
  CONCLUSIONS
  ETEC isolates that have the lngA gene showed features associated with self-aggregation, and adherence to HT-29 cells, important characteristics in the human gut colonization process and pathogenesis.
authors: Unidad de Hemato-Onocología e Investigación, Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México Federico Gómez Mexico City, Mexico.
authors: Ariadnna
authors: A
authors: Cruz-Córdova
authors: Unidad de Hemato-Onocología e Investigación, Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México Federico Gómez Mexico City, Mexico.
authors: Karina
authors: K
authors: Espinosa-Mazariego
authors: Unidad de Hemato-Onocología e Investigación, Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México Federico Gómez Mexico City, Mexico.
authors: Sara A
authors: SA
authors: Ochoa
authors: Unidad de Hemato-Onocología e Investigación, Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México Federico Gómez Mexico City, Mexico ; Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México Mexico City, Mexico.
authors: Zeus
authors: Z
authors: Saldaña
authors: Unidad de Hemato-Onocología e Investigación, Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México Federico Gómez Mexico City, Mexico ; Departamento de Genética Molecular, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México Mexico City, Mexico.
authors: Gerardo E
authors: GE
authors: Rodea
authors: Unidad de Hemato-Onocología e Investigación, Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México Federico Gómez Mexico City, Mexico.
authors: Vicenta
authors: V
authors: Cázares-Domínguez
authors: Unidad de Hemato-Onocología e Investigación, Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México Federico Gómez Mexico City, Mexico.
authors: Viridiana
authors: V
authors: Rodríguez-Ramírez
authors: Unidad de Hemato-Onocología e Investigación, Laboratorio de Patogenicidad Bacteriana, Hospital Infantil de México Federico Gómez Mexico City, Mexico ; Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional Autónoma de México Mexico City, Mexico.
authors: Carlos A
authors: CA
authors: Eslava-Campos
authors: Departamento de Salud Pública, Facultad de Medicina, Universidad Nacional Autónoma de México Mexico City, Mexico.
authors: Armando
authors: A
authors: Navarro-Ocaña
authors: Laboratorio de Infectología, Departamento de Infectología, Hospital Infantil de México Federico Gómez Mexico City, Mexico.
authors: José
authors: J
authors: Arrellano-Galindo
authors: Departamento de Ecología de Agentes Patógenos, Hospital General "Dr. Manuel Gea González," Mexico City, Mexico.
authors: Rigoberto
authors: R
authors: Hernández-Castro
authors: Department of Pediatrics, Division of Pediatric Infectious Diseases, Vanderbilt University School of Medicine Nashville, TN, USA.
authors: Oscar G
authors: OG
authors: Gómez-Duarte
authors: Centre for Vaccine Sciences, International Centre for Diarrhoeal Disease Research Dhaka, Bangladesh.
authors: Firdausi
authors: F
authors: Qadri
authors: Unidad de Hemato-Onocología e Investigación, Laboratorio de Investigación en Bacteriología Intestinal, Hospital Infantil de México Federico Gómez Mexico City, Mexico.
authors: Juan
authors: J
authors: Xicohtencatl-Cortes
keywords: CS21; ETEC; biofilm; multidrug-resistance; self-aggregation and adherence
references: Wkly Epidemiol Rec. 2006 Mar 17;81(11):97-104
references: 16671213
references: Clin Microbiol Rev. 2005 Jul;18(3):465-83
references: 16020685
references: Science. 1991 Nov 1;254(5032):710-3
references: 1683004
references: J Clin Invest. 2007 Nov;117(11):3519-29
references: 17948128
references: Nature. 1970 Aug 15;227(5259):680-5
references: 5432063
references: Am J Trop Med Hyg. 2010 Aug;83(2):292-7
references: 20682870
references: Vaccine. 1995 Jul;13(10):939-46
references: 7483768
references: Clin Microbiol Rev. 1998 Jan;11(1):142-201
references: 9457432
references: Microbiology. 2013 Aug;159(Pt 8):1725-35
references: 23760820
references: Cell. 2006 Feb 24;124(4):715-27
references: 16497583
references: Infect Immun. 1984 Mar;43(3):959-65
references: 6199307
references: J Bacteriol. 2010 Jun;192(11):2791-800
references: 20348256
references: J Clin Diagn Res. 2014 May;8(5):DC09-11
references: 24995174
references: N Z Med J. 1985 Nov 13;98(790):965
references: 3909022
references: Infect Immun. 1995 Oct;63(10):4195-8
references: 7558343
references: Infect Immun. 2001 Sep;69(9):5864-73
references: 11500465
references: J Clin Microbiol. 2000 May;38(5):1767-71
references: 10790096
references: J Bacteriol. 2007 Dec;189(24):9145-9
references: 17951389
references: Travel Med Infect Dis. 2009 Nov;7(6):337-43
references: 19945010
references: Am J Trop Med Hyg. 2006 May;74(5):891-900
references: 16687698
references: J Health Popul Nutr. 2004 Dec;22(4):370-82
references: 15663170
references: J Infect Dev Ctries. 2013 Feb 15;7(2):90-100
references: 23416654
references: Braz J Microbiol. 2012 Jul;43(3):969-80
references: 24031915
references: FEMS Microbiol Lett. 2006 Oct;263(1):10-20
references: 16958845
references: Proc Natl Acad Sci U S A. 1987 May;84(9):2833-7
references: 2883655
references: Environ Microbiol. 2009 Apr;11(4):992-1006
references: 19187284
references: Nat Rev Microbiol. 2010 Jan;8(1):26-38
references: 19966814
references: Mol Microbiol. 1994 Apr;12(1):71-82
references: 7914665
references: J Chemother. 2015 Jun;27(3):152-5
references: 24571245
references: Infect Immun. 1985 Oct;50(1):255-61
references: 2864313
references: J Antimicrob Chemother. 2002 Jan;49(1):25-30
references: 11751763
references: J Clin Microbiol. 2002 Jul;40(7):2606-8
references: 12089285
references: J Appl Microbiol. 2007 May;102(5):1187-96
references: 17448154
references: Biomed Res Int. 2014;2014:236260
references: 24877071
references: Gene. 1997 Jun 11;192(1):39-43
references: 9224872
references: Microb Pathog. 2010 Jun;48(6):230-8
references: 20227481
references: Trends Microbiol. 2008 Nov;16(11):535-42
references: 18819802
references: J Clin Microbiol. 2002 Feb;40(2):694-7
references: 11826000
references: Nat Rev Microbiol. 2004 May;2(5):363-78
references: 15100690
references: Trans N Y Acad Sci. 1965 Jun;27(8):1003-54
references: 5318403
references: Vaccine. 2011 Aug 26;29(37):6167-78
references: 21723899
references: Proc Natl Acad Sci U S A. 2000 Jun 6;97(12):6640-5
references: 10829079
references: Trends Microbiol. 1996 Nov;4(11):444-52
references: 8950814
references: J Infect Dis. 1981 Mar;143(3):325-45
references: 7014727
references: J Control Release. 2014 Sep 28;190:607-23
references: 24794896