Streptococcus pneumoniae detects and responds to foreign bacterial peptide fragments in its environment

Streptococcus pneumoniae is an important cause of bacterial meningitis and pneumonia but usually colonizes the human nasopharynx harmlessly. As this niche is simultaneously populated by other bacterial species, we looked for a role and pathway of communication between pneumococci and other species. This paper shows that two proteins of non-encapsulated S. pneumoniae, AliB-like ORF 1 and ORF 2, bind specifically to peptides matching other species resulting in changes in the pneumococci. AliB-like ORF 1 binds specifically peptide SETTFGRDFN, matching 50S ribosomal subunit protein L4 of Enterobacteriaceae, and facilitates upregulation of competence for genetic transformation. AliB-like ORF 2 binds specifically peptides containing sequence FPPQS, matching proteins of Prevotella species common in healthy human nasopharyngeal microbiota. We found that AliB-like ORF 2 mediates the early phase of nasopharyngeal colonization in vivo. The ability of S. pneumoniae to bind and respond to peptides of other bacterial species occupying the same host niche may play a key role in adaptation to its environment and in interspecies communication. These findings reveal a completely new concept of pneumococcal interspecies communication which may have implications for communication between other bacterial species and for future interventional therapeutics.

Frontières - théâtre-essai

Certes la distinction tranchée entre tragédie et comédie n’a plus cours, par contre si vous essayez de ronger les frontières entre essai, roman, théâtre, poésie, quel tollé», écrivait Michel Butor. Pour représenter la multiplicité des frontières, il a pourtant été nécessaire dans ce livre de convoquer une écriture située elle-même aux frontières des genres, polyphonique, procédant par montage et rapprochements de voix éparses, selon un principe de choralité. En est né un genre hybride, le «théâtre-essai» (à la façon dont certains vidéastes pratiquent le «vidéo-essai»). En tant qu’essai, ce livre repose sur une base documentaire, qui a porté d’une part sur la figuration des frontières en littérature et dans les arts, d’autre part sur les approches des frontières par les différents domaines du savoir (géographie, droit, polémologie, sociologie, anthropologie et écologie). Mais c’est à travers le langage théâtral lui-même, tant sur le plan textuel que de l’organisation de l’espace, que les frontières sont ici interrogées : celles qui séparent le littéraire du non-littéraire, ou la salle de la scène.

Fragments from Graeco-Jewish writers

collected and ed. with brief introd. and notes by Wallace Nelson Stearns

Essai sur la régénération physique, morale et politique des juifs

par [Henri] Grégoire

Judaica seu veterum scriptorum profanorum de rebus Judaicis fragments

coll. Fr. Carolus Meier

Les Juifs dans le moyen âge : essai historique sur leur état civil, commercial et littéraire ...

par G. B. Depping

Essai sur le Judaisme, son passé et son avenir

par Israel-Michel Rabbinowicz

Bibliothèque de l'Institut de Carthage : la literature populaire des Israélites tunisiens avec un essai ethnographique et archèologique sur leurs supersitions

par Eusèbe Vassel

Liberales Judentum : ein Essai

von Claude G. Montefiore. Einzig autor. deutsche Übers. von Oscar Plaut

tRNA-derived fragments target the small ribosomal subunit to fine-tune translation

Post-transcriptional cleavage of RNA molecules to generate smaller fragments is a widespread mechanism that enlarges the structural and functional complexity of cellular RNomes. In particular, fragments deriving from both precursor and mature tRNAs represent one of the rapidly growing classes of post-transcriptional RNA pieces. Importantly, these tRNA-derived fragments (tRFs) possess distinct expression patterns, abundance, cellular localizations, or biological roles compared with their parental tRNA molecules (1). Here we present evidence that tRFs from the archaeon Haloferax volcanii directly bind to ribosomes. In a previous genomic screen for ribosome-associated small RNAs we have identified a 26 residue long fragment originating from the 5’ part of valine tRNA (Val-tRF) to be by far the most abundant tRF in H. volcanii (2). The Val-tRF is processed in a stress- dependent manner and was found to primarily target the small ribosomal subunit in vitro and in vivo. Translational activity was markedly reduced in the presence of Val-tRF, while control RNA fragments of similar length did not show inhibition of protein biosynthesis. Crosslinking experiments and subsequent primer extension analyses revealed the Val-tRF interaction site to surround the mRNA path in the 30S subunit. In support of this, binding experiments demonstrated that Val-tRF does compete with mRNAs for ribosome binding. Therefore this tRF represents a ribosome-bound non-protein-coding RNA (ncRNA) capable of regulating gene expression in H. volcanii under environmental stress conditions probably by fine-tuning the rate of protein production (1). (1) Gebetsberger J. and Polacek N. (2013), RNA Biol. 10:1798-1808 (2) Gebetsberger J. et. al. (2012), Archaea, Article ID 260909

Predicting prostate cancer-specific outcome after radical prostatectomy among men with very high-risk cT3b/4 PCa: a multi-institutional outcome study of 266 patients

BACKGROUND The value of radical prostatectomy (RP) as an approach for very high-risk prostate cancer (PCa) patients is controversial. To examine the risk of 10-year cancer-specific mortality (CSM) and other-cause mortality (OCM) according to clinical and pathological characteristics of very high-risk cT3b/4 PCa patients treated with RP as the primary treatment option. METHODS In a multi-institutional cohort, 266 patients with very high-risk cT3b/4 PCa treated with RP were identified. All patients underwent RP and pelvic lymph-node dissection. Competing-risk analyses assessed 10-year CSM and OCM before and after stratification for age and Charlson comorbidity index (CCI). RESULTS Overall, 34 (13%) patients died from PCa and 73 (28%) from OCM. Ten-year CSM and OCM rates ranged from 5.6% to 12.9% and from 10% to 38%, respectively. OCM was the leading cause of death in all subgroups. Age and comorbidities were the main determinants of OCM. In healthy men, CSM rate did not differ among age groups (10-year CSM rate for ⩽64, 65-69 and ⩾70 years: 16.2%, 11.5% and 17.1%, respectively). Men with a CCI ⩾1 showed a very low risk of CSM irrespective of age (10-year CSM: 5.6-6.1%), whereas the 10-year OCM rates increased with age up to 38% in men ⩾70 years. CONCLUSION Very high-risk cT3b/4 PCa represents a heterogeneous group. We revealed overall low CSM rates despite the highly unfavorable clinical disease. For healthy men, CSM was independent of age, supporting RP even for older men. Conversely, less healthy patients had the highest risk of dying from OCM while sharing very low risk of CSM, indicating that this group might not benefit from an aggressive surgical treatment. Outcome after RP as the primary treatment option in cT3b/4 PCa patients is related to age and comorbidity status.

La France juive : essai d'histoire contemporaine

Edouard Drumont

Essai sur l'histoire des Israélites de l'Empire Ottoman depuis les origines jusqu'à nos jours

par M. Franco