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Strengthening of enterococcal biofilms by Esp

Profile image of Elizabeth MontanoElizabeth Montano
https://doi.org/10.1101/2022.06.09.495547
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Abstract

Multidrug-resistant (MDR) Enterococcus faecalis are major causes of hospital-acquired infections. Numerous clinical strains harbor a large pathogenicity island that encodes enterococcal surface protein (Esp), which is suggested to promote biofilm production and virulence, but this remains controversial. To resolve this issue, we characterized the Esp N-terminal region, the portion implicated in biofilm production. Small angle X-ray scattering indicated that the N-terminal region had a globular head, which consisted of two DEv-Ig domains as visualized by X-ray crystallography, followed by an extended tail. The N-terminal region was not required for biofilm production but instead significantly strengthened biofilms against mechanical or degradative disruption, greatly increasing retention of Enterococcus within biofilms. Biofilm strengthening required low pH, which resulted in Esp unfolding, aggregating, and forming amyloid-like structures. The pH threshold for biofilm strengthening d...

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  58. Barnes AMT, Dale JL, Chen Y, Manias DA, Greenwood Quaintance KE, Karau MK, Kashyap PC, Patel R, Wells CL, Dunny GM. Enterococcus faecalis readily colonizes the entire gastrointestinal tract and forms biofilms in a germ-free mouse model. Virulence. 2017;8(3):282-96. PMC5411234. PubMed 27562711
  59. Dressman JB, Berardi RR, Dermentzoglou LC, Russell TL, Schmaltz SP, Barnett JL, Jarvenpaa KM. Upper gastrointestinal (GI) pH in young, healthy men and women. Pharm Res. 1990;7(7):756-61. PubMed 2395805
  60. Hojo S, Komatsu M, Okuda R, Takahashi N, Yamada T. Acid profiles and pH of carious dentin in active and arrested lesions. J Dent Res. 1994;73(12):1853-7. PubMed 7814758
  61. 10 Fuca1-2Galb1-3(Fuca1-4)GlcNAcb-Sp8
  62. Fuca1-2Galb1-3GalNAcb1-4(Neu5Aca2-3)Galb1-4Glcb-Sp0 12
  63. Fuca1-2Galb1-3GalNAcb1-4(Neu5Aca2-3)Galb1-4Glcb-Sp9 5
  64. Fuca1-2Galb1-3GlcNAcb1-3Galb1-4Glcb-Sp10
  65. Fuca1-2Galb1-4(Fuca1-3)GlcNAcb1-3Galb1-4(Fuca1-3)GlcNAcb-Sp0 13 11
  66. Fuca1-2Galb1-4(Fuca1-3)GlcNAcb1-3Galb1-4(Fuca1-3)GlcNAcb1- 3Galb1-4(Fuca1-3)GlcNAcb-Sp0 45 32
  67. Fuca1-2Galb1-4(Fuca1-3)GlcNAcb-Sp8 15
  68. Fuca1-2Galb-Sp8 24
  69. Fuca1-3GlcNAcb-Sp8 12
  70. Fuca1-4GlcNAcb-Sp8 55
  71. GalNAca1-3(Fuca1-2)Galb1-3GlcNAcb-Sp0 51 23
  72. GalNAca1-3(Fuca1-2)Galb1-4(Fuca1-3)GlcNAcb-Sp0 102 72 (3S)Galb1-4(Fuca1-3)Glcb-Sp0 20
  73. GalNAca1-3(Fuca1-2)Galb1-4GlcNAcb-Sp0 9
  74. GalNAca1-3(Fuca1-2)Galb1-4GlcNAcb-Sp8 5
  75. GalNAca1-3(Fuca1-2)Galb1-4Glcb-Sp0 4
  76. GalNAca1-3(Fuca1-2)Galb-Sp8 5
  77. GalNAca1-3(Fuca1-2)Galb-Sp18 18 12 GalNAca1-3GalNAcb-Sp8
  78. GalNAca1-4(Fuca1-2)Galb1-4GlcNAcb-Sp8
  79. GalNAcb1-3(Fuca1-2)Galb-Sp8 14
  80. GalNAcb1-3Gala1-4Galb1-4GlcNAcb-Sp0 16
  81. Gala1-2Galb-Sp8 44 14
  82. Gala1-3(Fuca1-2)Galb1-3GlcNAcb-Sp0 20 13
  83. Gala1-3(Fuca1-2)Galb1-3GlcNAcb-Sp8 125 81
  84. Gala1-3(Fuca1-2)
  85. Galb1-4(Fuca1-3)GlcNAcb-Sp0 7
  86. Gala1-3(Fuca1-2)
  87. Galb1-4(Fuca1-3)GlcNAcb-Sp8 68 41
  88. Gala1-3(Fuca1-2)Galb1-4GlcNAc-Sp0 14 11
  89. Gala1-3(Fuca1-2)Galb1-4Glcb-Sp0 11
  90. Gala1-3(Fuca1-2)Galb-Sp8 16
  91. Gala1-3(Fuca1-2)Galb-Sp18 10 15
  92. Gala1-4(Gala1-3)Galb1-4GlcNAcb-Sp8 5 -9 Gala1-3GalNAca-Sp8 28 14 Gala1-3GalNAca-Sp16 98 43
  93. Gala1-3GalNAcb-Sp8 17
  94. Gala1-3Galb1-4(Fuca1-3)GlcNAcb-Sp8
  95. Gala1-3Galb1-4GlcNAcb-Sp8
  96. Gala1-3Galb-Sp8 15
  97. Gala1-4(Fuca1-2)Galb1-4GlcNAcb-Sp8 -1
  98. Gala1-4Galb1-4GlcNAcb-Sp8
  99. Gala1-4GlcNAcb-Sp8 31 28
  100. Gala1-6Glcb-Sp8 33 15
  101. Galb1-2Galb-Sp8 1
  102. Galb1-3(Fuca1-4)GlcNAcb1-3Galb1-4(Fuca1-3)GlcNAcb-Sp0 6
  103. Galb1-3GlcNAcb1-3Galb1-4(Fuca1-3)GlcNAcb-Sp0 6
  104. Galb1-3(Fuca1-4)GlcNAc-Sp0 38 13
  105. Galb1-3(Fuca1-4)GlcNAc-Sp8 12
  106. Fuca1-4(Galb1-3)GlcNAcb-Sp8 14
  107. GlcNAcb1-6(Galb1-3)GalNAca-Sp8 16
  108. GlcNAcb1-6(Galb1-3)GalNAca-Sp14 4 -1 Neu5Aca2-6(Galb1-3)GalNAca-Sp8 3
  109. Neu5Aca2-6(Galb1-3)GalNAca-Sp14 32 15
  110. Neu5Acb2-6(Galb1-3)GalNAca-Sp8 9
  111. Neu5Aca2-6(Galb1-3)GlcNAcb1-4Galb1-4Glcb-Sp10 -2
  112. Galb1-3GalNAca-Sp8 21
  113. Galb1-3GalNAcb1-4(Neu5Aca2-3)Galb1-4Glcb-Sp0
  114. Galb1-3GlcNAcb-Sp8 29 14
  115. Galb1-4(Fuca1-3)GlcNAcb-Sp0 10
  116. Galb1-4(Fuca1-3)GlcNAcb-Sp8 12
  117. Galb1-4(Fuca1-3)GlcNAcb1-3Galb1-4(Fuca1-3)GlcNAcb-Sp0 17
  118. Galb1-4(Fuca1-3)GlcNAcb1-3Galb1-4(Fuca1-3)GlcNAcb1-3Galb1- 4(Fuca1-3)GlcNAcb-Sp0 6
  119. Galb1-4(6S)Glcb-Sp8 Neu5Aca2-3Galb1-4GlcNAcb1-2Mana1-6(Neu5Aca2-6Galb1- 4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4GlcNAcb-Sp12 -4
  120. Galb1-4(Fuca1-3)GlcNAcb1-2Mana1-6(Galb1-4(Fuca1-3)GlcNAcb1- 2Mana1-3)Manb1-4GlcNAcb1-4GlcNAcb-Sp20 23 10 Neu5,9Ac2a2-3Galb1-4GlcNAcb-Sp0 79 44 Neu5,9Ac2a2-3Galb1-3GlcNAcb-Sp0
  121. 0 Neu5Aca2-6Galb1-4GlcNAcb1-3Galb1-3GlcNAcb-Sp0 -29 -10 Neu5Aca2-3Galb1-3(Fuca1-4)GlcNAcb1-3Galb1-3(Fuca1-4)GlcNAcb- Sp0 14
  122. GalNAca1-3(Fuca1-2)Galb1-4GlcNAcb1-3Galb1-4GlcNAcb-Sp0 -1
  123. GalNAca1-3(Fuca1-2)Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb-Sp0 69 63
  124. Neu5Aca2-3Galb1-4(Fuca1-3)GlcNAcb1-6(Neu5Aca2-3Galb1-3)GalNAc- Sp14 56 46
  125. GlcNAca1-4Galb1-4GlcNAcb1-3Galb1-4(Fuca1-3)GlcNAcb1-3Galb1- 4(Fuca1-3)GlcNAcb-Sp0 67 33
  126. GlcNAca1-4Galb1-3GalNAc-Sp14 20
  127. Mana1-6(Neu5Aca2-6Galb1-4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1- 4GlcNAc-Sp12
  128. Mana1-6(Galb1-4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4GlcNAcb- Sp12 15
  129. GlcNAcb1-2Mana1-6(GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1-
  130. GlcNAcb-Sp22 63
  131. 350 Galb1-4GlcNAcb1-2Mana1-6(Galb1-4GlcNAcb1-2Mana1-3)Manb1- 4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp22
  132. 351 Galb1-3GlcNAcb1-2Mana1-6(Galb1-3GlcNAcb1-2Mana1-3)Manb1- 4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp22 40 352 (6S)GlcNAcb1-3Galb1-4GlcNAcb-Sp0
  133. 353 KDNa2-3Galb1-4(Fuca1-3)GlcNAc-Sp0
  134. 357 Fuca1-2Galb1-3GlcNAcb1-2Mana1-6(Fuca1-2Galb1-3GlcNAcb1- 2Mana1-3)Manb1-4GlcNAcb1-4GlcNAcb-Sp20
  135. 359 Fuca1-2Galb1-4(Fuca1-3)GlcNAcb1-2Mana1-6(Fuca1-2Galb1-4(Fuca1-
  136. 362 Fuca1-4(Galb1-3)GlcNAcb1-2Mana1-6(Fuca1-4(Galb1-3)GlcNAcb1- 2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp22 145 363 Neu5Aca2-6GlcNAcb1-4GlcNAc-Sp21
  137. 365 Galb1-4(Fuca1-3)GlcNAcb1-6(Fuca1-2Galb1-4GlcNAcb1-3)Galb1-4Glc- Sp21 27
  138. 366 Galb1-4GlcNAcb1-2Mana1-6(Galb1-4GlcNAcb1-4(Galb1-4GlcNAcb1-
  139. 367 GalNAca1-3(Fuca1-2)Galb1-4GlcNAcb1-2Mana1-6(GalNAca1-3(Fuca1-
  140. 368 Gala1-3(Fuca1-2)Galb1-4GlcNAcb1-2Mana1-6(Gala1-3(Fuca1-2)Galb1- 4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4GlcNAcb-Sp20
  141. 369 Gala1-3Galb1-4(Fuca1-3)GlcNAcb1-2Mana1-6(Gala1-3Galb1-4(Fuca1-
  142. 370 GalNAca1-3(Fuca1-2)Galb1-3GlcNAcb1-2Mana1-6(GalNAca1-3(Fuca1-
  143. 371 Fuca1-4(Fuca1-2Galb1-3)GlcNAcb1-2Mana1-3(Fuca1-4(Fuca1-2Galb1-
  144. 374 Neu5Aca2-3Galb1-4(Fuca1-3)GlcNAcb1-3GalNAca-Sp14
  145. Manb1-4GlcNAcb1-4GlcNAc-Sp12
  146. 376 Galb1-3GalNAca1-3(Fuca1-2)Galb1-4Glc-Sp0
  147. 377 Galb1-3GalNAca1-3(Fuca1-2)Galb1-4GlcNAc-Sp0
  148. 378 Galb1-3GlcNAcb1-3Galb1-4GlcNAcb1-6(Galb1-3GlcNAcb1-3)Galb1- 4Glcb-Sp0
  149. 379 Galb1-4(Fuca1-3)GlcNAcb1-6(Galb1-3GlcNAcb1-3)Galb1-4Glc-Sp21
  150. 380 Galb1-4GlcNAcb1-6(Fuca1-4(Fuca1-2Galb1-3)GlcNAcb1-3)Galb1-4Glc- Sp21 79
  151. 381 Galb1-4(Fuca1-3)GlcNAcb1-6(Fuca1-4(Fuca1-2Galb1-3)GlcNAcb1- 3)Galb1-4Glc-Sp21
  152. 382 Galb1-3GlcNAcb1-3Galb1-4(Fuca1-3)GlcNAcb1-6(Galb1-3GlcNAcb1- 3)Galb1-4Glc-Sp21
  153. 383 Galb1-4GlcNAcb1-6(Galb1-4GlcNAcb1-2)Mana1-6(Galb1-4GlcNAcb1- 4(Galb1-4GlcNAcb1-2)Mana1-3)Manb1-4GlcNAcb1-4GlcNAcb-Sp21
  154. 384 GlcNAcb1-2Mana1-6(GlcNAcb1-4(GlcNAcb1-2)Mana1-3)Manb1- 4GlcNAcb1-4GlcNAc-Sp21
  155. 385 Fuca1-2Galb1-3GalNAca1-3(Fuca1-2)Galb1-4Glcb-Sp0
  156. 386 Fuca1-2Galb1-3GalNAca1-3(Fuca1-2)Galb1-4GlcNAcb-Sp0
  157. 387 Galb1-3GlcNAcb1-3GalNAca-Sp14
  158. 389 GalNAca1-3(Fuca1-2)Galb1-3GalNAca1-3(Fuca1-2)Galb1-4GlcNAcb- Sp0
  159. 390 Gala1-3Galb1-3GlcNAcb1-2Mana1-6(Gala1-3Galb1-3GlcNAcb1- 2Mana1-3)Manb1-4GlcNAcb1-4GlcNAc-Sp19
  160. Gala1-3Galb1-3(Fuca1-4)GlcNAcb1-2Mana1-6(Gala1-3Galb1-3(Fuca1-
  161. GlcNAcb1-2Mana1-6(Galb1-4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1- 4GlcNAc-Sp12 23
  162. 3 Neu5Aca2-3Galb1-3GlcNAcb1-3GalNAca-Sp14 36 21
  163. Fuca1-2Galb1-4GlcNAcb1-3GalNAca-Sp14 42 32
  164. Galb1-4(Fuca1-3)GlcNAcb1-3GalNAca-Sp14 50 37
  165. Galb1-3GlcNAcb1-6Galb1-4GlcNAcb-Sp0
  166. 2 Galb1-3GlcNAca1-6Galb1-4GlcNAcb-Sp0 6 -2 GalNAcb1-3Gala1-6Galb1-4Glcb-Sp8 15
  167. Gala1-3(Fuca1-2)
  168. Galb1-4(Fuca1-3)Glcb-Sp21 44 13
  169. Galb1-4GlcNAcb1-6(Neu5Aca2-6Galb1-3GlcNAcb1-3)Galb1-4Glc-Sp21 28 16
  170. Gala1-3(Fuca1-2)Galb1-4GlcNAcb1-3GalNAca-Sp14 7
  171. GalNAca1-3(Fuca1-2)Galb1-4GlcNAcb1-3GalNAca-Sp14 18 14
  172. Fuca1-2Galb1-4(Fuca1-3)GlcNAcb1-3GalNAca-Sp14 227 168 Gala1-3(Fuca1-2)Galb1-4(Fuca1-3)GlcNAcb1-3GalNAc-Sp14 50 51
  173. GalNAca1-3(Fuca1-2)Galb1-4(Fuca1-3)GlcNAcb1-3GalNAc-Sp14 155 106
  174. Galb1-4(Fuca1-3)GlcNAcb1-2Mana1-6(Galb1-4(Fuca1-3)GlcNAcb1- 2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp22 57 26
  175. Fuca1-2Galb1-4GlcNAcb1-2Mana1-6(Fuca1-2Galb1-4GlcNAcb1- 2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp22 142 123 GlcNAcb1-2(GlcNAcb1-6)Mana1-6(GlcNAcb1-2Mana1-3)Manb1- 4GlcNAcb1-4GlcNAcb-Sp19
  176. 9 Fuca1-2Galb1-3GlcNAcb1-3GalNAc-Sp14
  177. 9 Gala1-3(Fuca1-2)Galb1-3GlcNAcb1-3GalNAc-Sp14 15
  178. GalNAca1-3(Fuca1-2)Galb1-3GlcNAcb1-3GalNAc-Sp14 92 58 Gala1-3Galb1-3GlcNAcb1-3GalNAc-Sp14 4
  179. Fuca1-2Galb1-3GlcNAcb1-2Mana1-6(Fuca1-2Galb1-3GlcNAcb1- 2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp22 150 94
  180. Gala1-3(Fuca1-2)Galb1-4GlcNAcb1-2Mana1-6(Gala1-3(Fuca1-2)Galb1- 4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp22 200 175 Galb1-3GlcNAcb1-6(Galb1-3GlcNAcb1-2)Mana1-6(Galb1-3GlcNAcb1- 2Mana1-3)Manb1-4GlcNAcb1-4GlcNAcb-Sp19 43
  181. Galb1-4GlcNAcb1-6(Fuca1-2Galb1-3GlcNAcb1-3)Galb1-4Glc-Sp21 30 18
  182. Fuca1-3GlcNAcb1-6(Galb1-4GlcNAcb1-3)Galb1-4Glc-Sp21 43 19
  183. GlcNAcb1-2Mana1-6(GlcNAcb1-4)(GlcNAcb1-2Mana1-3)Manb1- 4GlcNAcb1-4GlcNAc-Sp21 81 18
  184. GlcNAcb1-2Mana1-6(GlcNAcb1-4)(GlcNAcb1-4(GlcNAcb1-2)Mana1-
  185. Manb1-4GlcNAcb1-4GlcNAc-Sp21 23 10
  186. GlcNAcb1-6(GlcNAcb1-2)Mana1-6(GlcNAcb1-4)(GlcNAcb1-2Mana1-
  187. Manb1-4GlcNAcb1-4GlcNAc-Sp21 26 12
  188. GlcNAcb1-6(GlcNAcb1-2)Mana1-6(GlcNAcb1-4)(GlcNAcb1-4(GlcNAcb1-
  189. Mana1-3)Manb1-4GlcNAcb1-4GlcNAc-Sp21 31 25
  190. Galb1-4GlcNAcb1-2Mana1-6(GlcNAcb1-4)(Galb1-4GlcNAcb1-2Mana1-
  191. Manb1-4GlcNAcb1-4GlcNAc-Sp21 48 20
  192. Galb1-4GlcNAcb1-2Mana1-6(GlcNAcb1-4)(Galb1-4GlcNAcb1-4(Galb1- 4GlcNAcb1-2)Mana1-3)Manb1-4GlcNAcb1-4GlcNAc-Sp21 31 22
  193. Galb1-4GlcNAcb1-6(Galb1-4GlcNAcb1-2)Mana1-6(GlcNAcb1-4)(Galb1- 4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4GlcNAc-Sp21 36 22
  194. Galb1-4GlcNAcb1-6(Galb1-4GlcNAcb1-2)Mana1-6(GlcNAcb1-4)(Galb1- 4GlcNAcb1-4(Galb1-4GlcNAcb1-2)Mana1-3)Manb1-4GlcNAcb1- 4GlcNAc-Sp21 26 15
  195. Galb1-4Galb-Sp10 30 12
  196. Galb1-6Galb-Sp10 30 10 Neu5Aca2-3Galb1-4GlcNAcb1-3Galb-Sp8 10
  197. Fuca1-2Galb1-4 GlcNAcb1-2Mana1-6(Fuca1-2Galb1-4GlcNAcb1- 2(Fuca1-2Galb1-4GlcNAcb1-4)Mana1-3)Manb1-4GlcNAcb1-4GlcNAcb- Sp12 86 73
  198. Fuca1-2Galb1-4(Fuca1-3)GlcNAcb1-2Mana1-6(Fuca1-2Galb1-4(Fuca1-
  199. GlcNAcb1-4(Fuca1-2Galb1-4(Fuca1-3)GlcNAcb1-2)Mana1-3)Manb1- 4GlcNAcb1-4GlcNAcb-Sp12 140 92
  200. Galb1-4(Fuca1-3)GlcNAcb1-6GalNAc-Sp14 104 68 Galb1-4GlcNAcb1-2Mana-Sp0 42
  201. Fuca1-2Galb1-4GlcNAcb1-6(Fuca1-2Galb1-4GlcNAcb1-3)GalNAc-Sp14 26 16
  202. Gala1-3(Fuca1-2)Galb1-4GlcNAcb1-6(Gala1-3(Fuca1-2)Galb1- 4GlcNAcb1-
  203. GalNAc-Sp14 3
  204. GalNAca1-3(Fuca1-2)Galb1-4GlcNAcb1-6(GalNAca1-3(Fuca1-2)Galb1- 4GlcNAcb1-
  205. GalNAc-Sp14 12
  206. GalNAca1-3(Fuca1-2)Galb1-4GlcNAcb1-2Mana1-6(GalNAca1-3(Fuca1-
  207. Galb1-4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAcb- Sp22 42 24
  208. Gala1-3(Fuca1-2)Galb1-3GlcNAcb1-2Mana1-6(Gala1-3(Fuca1-2)Galb1- 3GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp22 210 179 Neu5Aca2-6Galb1-4GlcNAcb1-6(Fuca1-2Galb1-3GlcNAcb1-3)Galb1- 4Glc-Sp21 26 24
  209. GalNAca1-3(Fuca1-2)Galb1-3GlcNAcb1-2Mana1-6(GalNAca1-3(Fuca1-
  210. Galb1-3GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAcb- Sp22 411 260 Galb1-4GlcNAcb1-6(Galb1-4GlcNAcb1-2)Mana1-6(Galb1-4GlcNAcb1- 2Mana1-3)Manb1-4GlcNAcb1-4GlcNAcb-Sp19 55 35
  211. Mana1-6(GlcNAcb1-4)(Neu5Aca2-3Galb1-4GlcNAcb1-2Mana1-
  212. Manb1-4GlcNAcb1-4GlcNAcb-Sp21 16
  213. Neu5Aca2-3Galb1-4GlcNAcb1-6(Neu5Aca2-3Galb1-4GlcNAcb1-
  214. Mana1-6(GlcNAcb1-4)(Neu5Aca2-3Galb1-4GlcNAcb1-4(Neu5Aca2- 3Galb1-4GlcNAcb1-2)Mana1-3)Manb1-4GlcNAcb1-4GlcNAcb-Sp21
  215. 7 Neu5Aca2-6Galb1-4GlcNAcb1-2Mana1-6(GlcNAcb1-4)(Neu5Aca2- 6Galb1-4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4GlcNAcb-Sp21 41 25
  216. Neu5Aca2-6Galb1-4GlcNAcb1-4Mana1-6(GlcNAcb1-4)(Neu5Aca2- 6Galb1-4GlcNAcb1-4(Neu5Aca2-6Galb1-4GlcNAcb1-2)Mana1-3)Manb1- 4GlcNAcb1-4GlcNAcb-Sp21 16 12 Neu5Aca2-6Galb1-4GlcNAcb1-6(Neu5Aca2-6Galb1-4GlcNAcb1-
  217. Mana1-6(GlcNAcb1-4)(Neu5Aca2-6Galb1-4GlcNAcb1-2Mana1-
  218. Mana1-6(GlcNAcb1-4)(Neu5Aca2-6Galb1-4GlcNAcb1-4(Neu5Aca2- 6Galb1-4GlcNAcb1-2)Mana1-3)Manb1-4GlcNAcb1-4GlcNAcb-Sp21 14
  219. Gala1-3(Fuca1-2)Galb1-3GalNAca-Sp8 13
  220. Gala1-3(Fuca1-2)Galb1-3GalNAcb-Sp8 11
  221. Glca1-6Glca1-6Glca1-6Glcb-Sp10 41 14 Glca1-4Glca1-4Glca1-4Glcb-Sp10 15 19 Neu5Aca2-3Galb1-4GlcNAcb1-6(Neu5Aca2-3Galb1-4GlcNAcb1-
  222. GalNAca-Sp14 -2 -4 Fuca1-2Galb1-4(Fuca1-3)GlcNAcb1-2Mana1-6(Fuca1-2Galb1-4(Fuca1-
  223. GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp24 3 24
  224. Fuca1-2Galb1-3(Fuca1-4)GlcNAcb1-2Mana1-6(Fuca1-2Galb1-3(Fuca1- 4)
  225. GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAcb1- 4(Fuca1-6)GlcNAcb-Sp19 127 85
  226. GlcNAcb1-2 Mana1-6(GlcNAcb1-4)(GlcNAcb1-2Mana1-3)Manb1- 4GlcNAcb1-4(Fuca1-6)GlcNAc-Sp21 13
  227. Galb1-4GlcNAcb1-2 Mana1-6(GlcNAcb1-4)(Galb1-4GlcNAcb1-2Mana1-
  228. Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAc-Sp21 19 12
  229. Galb1-4GlcNAcb1-2 Mana1-6(Galb1-4GlcNAcb1-4)(Galb1-4GlcNAcb1- 2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAc-Sp21 22 22
  230. Fuca1-4(Galb1-3)GlcNAcb1-2 Mana-Sp0 105 79 Neu5Aca2-3Galb1-4(Fuca1-3)GlcNAcb1-2Mana-Sp0 2
  231. GlcNAcb1-3Galb1-4GlcNAcb1-6(GlcNAcb1-3)Galb1-4GlcNAc-Sp0 3
  232. GalNAca1-3(Fuca1-2)Galb1-3GalNAcb1-3Gala1-4Galb1-4Glc-Sp21 14
  233. Gala1-3(Fuca1-2)Galb1-3GalNAcb1-3Gala1-4Galb1-4Glc-Sp21 44 24 Galb1-3GalNAcb1-3Gal-Sp21 30 13
  234. GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-6(GlcNAcb1-3Galb1-4GlcNAcb1- 2Mana1-3)Manb1-4GlcNAcb1-4GlcNAcb-Sp12 7
  235. GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-6(GlcNAcb1-3Galb1-4GlcNAcb1- 2Mana1-3)Manb1-4GlcNAcb1-4GlcNAcb-Sp25 172 98
  236. GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-6(GlcNAcb1- 3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1- 4GlcNAcb-Sp12 798 382 GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-6(GlcNAcb1- 3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1- 4GlcNAcb-Sp25 155 124 Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1- 6(Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-
  237. Manb1-4GlcNAcb1-4GlcNAcb-Sp24 152 102 Galb1-3GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-6(Galb1-3GlcNAcb1- 3Galb1-4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4GlcNAc-Sp25 82 60 Neu5Gca2-8Neu5Gca2-3Galb1-4GlcNAc-Sp0
  238. GlcNAcb1-3Galb1-4GlcNAcb1-6(GlcNAcb1-3Galb1-4GlcNAcb1-
  239. Mana1-6(GlcNAcb1-3Galb1-4GlcNAcb1-2Man a1-3)Manb1- 4GlcNAcb1-4GlcNAc-Sp24 217 149 Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-6(Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-2)Mana1-6(Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-
  240. Mana1-4GlcNAcb1-4GlcNAc-Sp24 121 69
  241. Gala1-3Galb1-4GlcNAcb1-2Mana1-6(Gala1-3Galb1-4GlcNAcb1- 2Mana1-3)Manb1-4GlcNAcb1-4GlcNAc-Sp24 176 175 GlcNAcb1-3Galb1-4GlcNAcb1-6(GlcNAcb1-3Galb1-3)GalNAca-Sp14 -1 -2 GalNAcb1-3GlcNAcb-Sp0
  242. 3 GalNAcb1-4GlcNAcb1-3GalNAcb1-4GlcNAcb-Sp0 -9 -6 GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1- 3Galb1-4GlcNAcb1-2Mana1-6(GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-3)Manb1- 4GlcNAcb1-4GlcNAcb-Sp25 48 68
  243. Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-6(Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1- 2Mana1-3)Manb1-4GlcNAcb1-4GlcNAcb-Sp25 72 57 GlcNAb1-3Galb1-3GalNAc-Sp14 -1 -3 Galb1-3GlcNAcb1-6(Galb1-3)GalNAc-Sp14 3
  244. Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-6(Galb1- 4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1- 3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1- 4GlcNAcb-Sp25 -1 -1
  245. GlcAb1-3Galb1-4GlcNAcb1-3Galb1-4Glc-Sp0 -1 -1 (3S)GlcAb1-3Galb1-4GlcNAcb1-2Mana-Sp0 0 -2 Galb1-3GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-6(Galb1- 3GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAb1-2)Mana1-6(Galb1- 3GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-3)Manb1- 4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp24 79 52
  246. Galb1-3GlcNAcb1-3Galb1-4GlcNAcb1-6(Galb1-3GlcNAcb1-3Galb1- 4GlcNAb1-2)Mana1-6(Galb1-3GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-
  247. Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp24 196 90
  248. GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-6(GlcNAcb1-3Galb1-4GlcNAcb1- 2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp24 178 87
  249. Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-6(Galb1-4GlcNAcb1- 3Galb1-4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAcb- Sp24 145 113 GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-6(GlcNAcb1- 3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1- 4(Fuca1-6)GlcNAcb-Sp24 12
  250. Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp24 31 42
  251. GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1- 2Mana1-6(GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp24 44 68
  252. Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-2Mana1-6(Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1- 6)GlcNAcb-Sp24 44 94
  253. GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1- 3Galb1-4GlcNAcb1-2Mana1-6(GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-3)Manb1- 4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp19 12 18
  254. Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-6(Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1- 2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp19 36 70
  255. Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-6(Galb1-4GlcNAcb1-3Galb1- 4GlcNAb1-2)Mana1-6(Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-
  256. Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp24 70 82
  257. GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-6(GlcNAcb1-3Galb1- 4GlcNAcb1-3Galb1-4GlcNAb1-2)Mana1-6(GlcNAcb1-3Galb1- 4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1- 6)GlcNAcb-Sp24 38 42
  258. Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-6(Galb1- 4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAb1-2)Mana1-6(Galb1- 4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-3)Manb1- 4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp24 110 70
  259. GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1- 6(GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAb1-
  260. Mana1-6(GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp24 34 42
  261. Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-6(Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-3Galb1-4GlcNAb1-2)Mana1-6(Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-3)Manb1- 4GlcNAcb1-4(Fuca1-6)GlcNAcb-Sp24 24 62
  262. GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1- 3Galb1-4GlcNAcb1-6(GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAb1-2)Mana1- 6(GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4(Fuca1- 6)GlcNAcb-Sp24 94
  263. Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-3Galb1-4GlcNAcb1-6(Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAb1-
  264. Mana1-6(Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1- 79 123 3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1- 4(Fuca1-6)GlcNAcb-Sp24 Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3GalNAca-Sp14 273 138 Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-6(Galb1-3)GalNAca-Sp14 285 180 Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-6(Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-
  265. GalNAca-Sp14 483 239 Neu5Aca2-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3GalNAca-Sp14 -7 -8 GlcNAcb1-3Galb1-4GlcNAcb1-3GalNAca-Sp14 -15 -7 GlcNAcb1-3Galb1-4GlcNAcb1-6(Galb1-3)GalNAca-Sp14
  266. 0 GlcNAcb1-3Galb1-4GlcNAcb1-6(GlcNAcb1-3Galb1-4GlcNAcb1-
  267. GalNAca-Sp14 -1
  268. Galb1-4GlcNAcb1-3Galb1-3GalNAca-Sp14
  269. 2 Neu5Aca2-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-6(Galb1-3)GalNAca- Sp14 101 59
  270. Neu5Aca2-6Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-6(Galb1-3)GalNAca- Sp14 45 189 Neu5Aca2-6Galb1-4GlcNAcb1-6(Galb1-3)GalNAca-Sp14
  271. 8 Neu5Aca2-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1- 6(Neu5Aca2-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-3)Manb1- 4GlcNAcb1-4GlcNAcb-Sp12 227 128 GlcNAcb1-6(Neu5Aca2-3Galb1-3)GalNAca-Sp14
  272. 1 Neu5Aca2-6Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-6(Neu5Aca2-6Galb1- 4GlcNAcb1-3Galb1-4GlcNAcb1-3)GalNAca-Sp14 141 73
  273. Neu5Aca2-6Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1- 2Mana1-6(Neu5Aca2-6Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4GlcNAcb-Sp12 443 296 Neu5Aca2-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1- 2Mana1-6(Neu5Aca2-3Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-3Galb1- 4GlcNAcb1-2Mana1-3)Manb1-4GlcNAcb1-4GlcNAcb-Sp12 684 490 Neu5Aca2-6Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1- 6(Neu5Aca2-6Galb1-4GlcNAcb1-3Galb1-4GlcNAcb1-2Mana1-3)Manb1- 4GlcNAcb1-4GlcNAcb-Sp12 119 67 GlcNAcb1-3Fuca-Sp21 1

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The enterococcal surface protein, Esp, is a high-molecular-weight surface protein of unknown function whose frequency is significantly increased among infection-derived Enterococcus faecalis isolates. In this work, a global structural similarity was found between Bap, a biofilm-associated protein of Staphylococcus aureus , and Esp. Analysis of the relationship between the presence of the Esp-encoding gene ( esp ) and the biofilm formation capacity in E. faecalis demonstrated that the presence of the esp gene is highly associated ( P &lt; 0.0001) with the capacity of E. faecalis to form a biofilm on a polystyrene surface, since 93.5% of the E. faecalis esp -positive isolates were capable of forming a biofilm. Moreover, none of the E. faecalis esp -deficient isolates were biofilm producers. Depending on the E. faecalis isolate, insertional mutagenesis of esp caused either a complete loss of the biofilm formation phenotype or no apparent phenotypic defect. Complementation studies revea...

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Esp-Independent Biofilm Formation by Enterococcus faecalis
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Enterococcus faecalis is a gram-positive opportunistic pathogen known to form biofilms in vitro. In addition, this organism is often isolated from biofilms on the surfaces of various indwelling medical devices. However, the molecular mechanisms regulating biofilm formation in these clinical isolates are largely unknown. Recent work has suggested that a specific cell surface protein (Esp) of E. faecalis is critical for biofilm formation by this organism. However, in the same study, esp-deficient strains of E. faecalis were found to be capable of biofilm formation. To test the hypothesis that Esp is dispensable for biofilm formation by E. faecalis, we used microtiter plate assays and a chemostat-based biofilm fermentor assay to examine biofilm formation by genetically well-defined, non-Esp-expressing strains. Our results demonstrate that in vitro biofilm formation occurs, not only in the absence of esp, but also in the absence of the entire pathogenicity island that harbors the esp coding sequence. Using scanning electron microscopy to evaluate biofilms of E. faecalis OG1RF grown in the fermentor system, biofilm development was observed to progress through multiple stages, including attachment of individual cells to the substratum, microcolony formation, and maturation into complex multilayered structures apparently containing water channels. Microtiter plate biofilm analyses indicated that biofilm formation or maintenance was modulated by environmental conditions. Furthermore, our results demonstrate that expression of a secreted metalloprotease, GelE, enhances biofilm formation by E. faecalis. In summary, E. faecalis forms complex biofilms by a process that is sensitive to environmental conditions and does not require the Esp surface protein.

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The biofilm-associated surface protein Esp of Enterococcus faecalis forms amyloid-like fibers
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Functional amyloids are considered as common building block structures of the biofilm matrix in different bacteria. In previous work, we have shown that the staphylococcal surface protein Bap, a member of the Biofilm-Associated Proteins (BAP) family, is processed and the fragments containing the N-terminal region become aggregation-prone and self-assemble into amyloid-like structures. Here, we report that Esp, a Bap-orthologous protein produced by Enterococcus faecalis, displays a similar amyloidogenic behavior. We demonstrate that at acidic pH the N-terminal region of Esp forms aggregates with an amyloid-like conformation, as evidenced by biophysical analysis and the binding of protein aggregates to amyloid-indicative dyes. Expression of a chimeric protein, with its Esp N-terminal domain anchored to the cell wall through the R domain of clumping factor A, showed that the Esp N-terminal region is sufficient to confer multicellular behavior through the formation of an extracellular a...

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Restructuring of Enterococcus faecalis biofilm architecture in response to antibiotic-induced stress
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Enterococcus species are known for their ability to form biofilms, which contributes to their survival in extreme environments and involvement in persistent bacterial infections, especially in the case of multi-drug-resistant strains. This review aims to provide a comprehensive understanding of the mechanisms underlying biofilm formation in clinically important species such as Enterococcus faecalis and the less studied but increasingly multi-drug-resistant Enterococcus faecium, and explores potential strategies for their eradication. Biofilm formation in Enterococcus involves a complex interplay of genes and virulence factors, including gelatinase, cytolysin, Secreted antigen A, pili, microbial surface components that recognize adhesive matrix molecules (MSCRAMMs), and DNA release. Quorum sensing, a process of intercellular communication, mediated by peptide pheromones such as Cob, Ccf, and Cpd, plays a crucial role in coordinating biofilm development by targeting gene expression an...

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