Draft Genome Sequence of an Antibiotic-Resistant Propionibacterium acnes Strain, PRP-38, from the Novel Type IC Cluster

Propionibacterium acnes, a non-spore-forming, anaerobic Gram-positive bacterium, is most notably recognized for its association with acne vulgaris (I. Kurokawa et al., Exp. Dermatol. 18:821–832, 2009). We now present the draft genome sequence of an antibiotic-resistantP. acnesstrain, PRP-38, isolated from an acne patient in the United Kingdom and belonging to the novel type IC cluster. Copyright © 2012, American Society for Microbiology. All Rights Reserved.

Multiplex Touchdown PCR for Rapid Typing of the Opportunistic Pathogen Propionibacterium acnes.

The opportunistic human pathogen Propionibacterium acnes is comprised of a number of distinct phylogroups, designated types IA1, IA2, IB, IC, II and III, that vary in their production of putative virulence factors, inflammatory potential, as well as biochemical, aggregative and morphological characteristics. Although Multilocus Sequence Typing (MLST) currently represents the gold standard for unambiguous phylogroup classification, and individual strain identification, it is a labour and time-consuming technique. As a consequence, we have developed a multiplex touchdown PCR assay that will, in a single reaction, confirm species identity and phylogeny of an isolate based on its pattern of reaction with six primer sets that target the 16S rRNA (all isolates), ATPase (type IA1, IA2, IC), sodA (type IA2, IB), atpD (type II) and recA (type III) housekeeping genes, as well as a Fic family toxin gene (type IC). When applied to 312 P. acnes isolates previously characterised by MLST, and representing type IA1 (n=145), IA2 (n=20), IB (n=65), IC (n=7), II (n=45) and III (n=30), the multiplex displayed 100% sensitivity and 100% specificity for the detection of isolates within each targeted phylogroup. No cross-reactivity with isolates from other bacterial species was observed. The multiplex assay will provide researchers with a rapid, high-throughput and technically undemanding typing method for epidemiological and phylogenetic investigations. It will facilitate studies investigating the association of lineages with various infections and clinical conditions, as well as a pre-screening tool to maximise the number of genetically diverse isolates selected for downstream, higher resolution sequence-based analyses.

Protein expression differences between lung adenocarcinoma and squamous cell carcinoma with brain metastasis

AIM: We investigated tissue biomarkers in non-small cell lung cancer (NSCLC) to find indicators of brain metastasis and peritumoral brain edema.

PATIENTS AND METHODS: Fifty-two cases were studied out of which 26 had corresponding brain metastatic tissue. Clinicopathological characteristics of tumors were correlated with biomarkers of cell adhesion, cell growth, cell cycle and apoptosis regulation that were previously immunohistochemically studied but never analyzed separately according to histological subgroups, gender and smoking history.

RESULTS: Increased collagen XVII in adenocarcinoma (ADC) and increased caspase-9, CD44v6, and decreased cellular apoptosis susceptibility protein (CAS) and Ki-67 in squamous cell carcinoma (SCC) correlated significantly with brain metastasis. Increased β-catenin, E-cadherin and decreased caspase-9 expression in primary SCC, and decreased CD44v6 expression in brain metastatic SCC tissues showed a significant correlation with the extent of peritumoral brain edema. Positive correlation between smoking and biomarker expression could be observed in metastatic ADCs with p16 and caspase-8, while-negative correlation was found in SCC without brain metastasis with caspase-3, and in SCC with brain metastasis with p27.

CONCLUSION: Our results highlight the importance of separate analysis of biomarker expression in histological subtypes of NSCLC.

Accumulation of the PX domain mutant Frank-ter Haar syndrome protein Tks4 in aggresomes

BACKGROUND: Cells deploy quality control mechanisms to remove damaged or misfolded proteins. Recently, we have reported that a mutation (R43W) in the Frank-ter Haar syndrome protein Tks4 resulted in aberrant intracellular localization.

RESULTS: Here we demonstrate that the accumulation of Tks4(R43W) depends on the intact microtubule network. Detergent-insoluble Tks4 mutant colocalizes with the centrosome and its aggregate is encaged by the intermediate filament protein vimentin. Both the microtubule inhibitor nocodazole and the histone deacetylase inhibitor Trichostatin A inhibit markedly the aggresome formation in cells expressing Tks4(R43W). Finally, pretreatment of cells with the proteasome inhibitor MG132 markedly increases the level of aggresomes formed by Tks4(R43W). Furthermore, two additional mutant Tks4 proteins (Tks4(1-48) or Tks4(1-341)) have been investigated. Whereas the shorter Tks4 mutant, Tks4(1-48), shows no expression at all, the longer Tks4 truncation mutant accumulates in the nuclei of the cells.

CONCLUSIONS: Our results suggest that misfolded Frank-ter Haar syndrome protein Tks4(R43W) is transported via the microtubule system to the aggresomes. Lack of expression of Tks4(1-48) or aberrant intracellular expressions of Tks4(R43W) and Tks4(1-341) strongly suggest that these mutations result in dysfunctional proteins which are not capable of operating properly, leading to the development of FTHS.