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The book draws on background papers prepared by Reehana Raza (skills development) and Dhushyanth Raju and Ritika Dsouza (private tutoring as well as public school teacher management in Sri Lanka). The peer reviewers for the report were Cem Mete and Juan Manuel Moreno. The team also benefited from advice, inputs, and comments from a number of individuals at critical points in the report's preparation, notably Chitral Amarasiri, Roshini Ebenezer, David Locke Newhouse, Yevgeniya Savchenko, Shalika Subasinghe, and Hassan Zaman. Many individuals from the Prime Minister's Office, the Ministry of Finance, the Ministry of National Policies and Economic Affairs, the Ministry of Women and Child Affairs, the Ministry of Education, the Ministry of Higher Education and Highways, and the Ministry of Skills Development and Vocational Training participated in and provided extremely useful insights at consultations and dissemination events. None of the people mentioned above bear any responsibility for the analyses and findings of this report. The authors alone assume full responsibility for its conclusions.

A novel antimicrobial peptide designated enterocin O16 was purified from Enterococcus faecalis. Mass spectrometry showed a monoisotopic mass of 7,231 Da, and N-terminal Edman degradation identified a 29-amino-acid sequence corresponding to residues 90 to 119 of the EF_1097 protein. Bioinformatic analysis showed that enterocin O16 is composed of the 68 most C-terminal residues of the EF_1097 protein. Introduction of an in-frame isogenic deletion in the ef1097 gene abolished the production of enterocin O16. Enterocin O16 has a narrow inhibitory spectrum, as it inhibits mostly lactobacilli. Apparently, E. faecalis is intrinsically resistant to the antimicrobial peptide, as no immunity connected to the production of enterocin O16 could be identified. ef1097 has previously been identified as one of three loci regulated by the fsr quorum-sensing system. The introduction of a nonsense mutation into fsrB consistently impaired enterocin O16 production, but externally added gelatinase biosynthesis-activating pheromone restored the antimicrobial activity. Functional genetic analysis showed that the EF_1097 proprotein is processed extracellularly into enterocin O16 by the metalloprotease GelE. Thus, it is evident that the fsr quorum-sensing system constitutes the regulatory unit that controls the expression of the EF_1097 precursor protein and the protease GelE and that the latter is required for the formation of enterocin O16. On the basis of these results, this study identified antibacterial antagonism as a novel aspect related to the function of fsr and provides a rationale for why ef1097 is part of the fsr regulon. IMPORTANCEThe fsr quorum-sensing system modulates important physiological functions in E. faecalis via the activity of GelE. The present study presents a new facet of fsr signaling. The system controls the expression of three primary target operons (fsrABCD, gelEsprE, and ef1097-ef1097b). We demonstrate that the concerted expression of these operons constitutes the elements necessary for the production of a bacteriocin-type peptide and that antimicrobial antagonism is an intrinsic function of fsr. The bacteriocin enterocin O16 consists of the 68 most C-terminal residues of the EF_1097 secreted proprotein. The GelE protease processes the EF_1097 proprotein into enterocin O16. In this manner, fsr signaling enables E. faecalis populations to express antimicrobial activity in a cell density-dependent manner. E nterococci are among the most common commensal lactic acid bacteria (LAB) in the gastrointestinal (GI) tracts of humans and animals. Throughout our lives, we receive frequent supplies of enterococci, especially from fermented foods (dairy, meat, and vegetable based). While some enterococci seem to establish themselves as part of the GI microbiota, most enterococcal strains only transiently inhabit the GI system. Enterococci are also prominent etiological agents of nosocomial infections (1). The increasing incidence of multiple-antibiotic-resistant nosocomial isolates makes the treatment of infection...

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Some rights reserved 1 2 3 4 17 16 15 14 This work is a product of the staff of The World Bank with external contributions. The findings, interpretations, and conclusions expressed in this work do not necessarily reflect the views of The World Bank, its Board of Executive Directors, or the governments they represent. The World Bank does not guarantee the accuracy of the data included in this work. The boundaries, colors, denominations, and other information shown on any map in this work do not imply any judgment on the part of The World Bank concerning the viii Contents Building the Skills for Economic Growth and Competitiveness in Sri Lanka