The Origin of Life Domain (OLD) is the period during which life on Earth began. Here, we derive and use a new phylogenetic algorithm to analyze Protein Families in order to reconstruct the chronological steps by which the OLD evolved. During this period, life began with the appearance of the fundamental components of life such as RNAs, DNAs, amino acids, and membranes. Chronologically, the Origin of Life preceded the Last Universal Common Ancestor, which then subsequently engendered modern life on Earth. Our phylogenetic algorithm allows us to explicitly answer previously unknown origin of life questions. Specifically, we explain and illustrate our computational methods by reconstructing the rings describing the evolution of the RNA and DNA worlds. We phylogenetically reconstruct how the RNA and DNA worlds evolved, infer the origins and chronological order of appearance of the first genetic codes, test whether the Ribosomal RNA world preceded the Membrane world, and interpret these new findings with respect to the experimental and theoretical origin of life studies by others.

Anthracimycin is a recently discovered novel marine-derived compound with activity against Bacillus anthracis. We tested anthracimycin against an expanded panel of Staphylococcus aureus strains in vitro and in vivo. All strains of S. aureus tested, including methicillin-susceptible, methicillin-resistant (MRSA) and vancomycin-resistant strains of S. aureus, were susceptible to anthracimycin at MIC values of ⩽0.25 mg l(-1). Although its postantibiotic effects were minimal, anthracimycin exhibited potent and rapid bactericidal activity, with a >4-log kill of USA300 MRSA within 3 h at five times its MIC. At concentrations significantly below the MIC, anthracimycin slowed MRSA growth and potentiated the bactericidal activity of the human cathelicidin, LL-37. The bactericidal activity of anthracimycin was somewhat mitigated in the presence of 20% human serum, and the compound was minimally toxic to human cells, with an IC50 (inhibitory concentration 50)=70 mg l(-1) against human carcinoma cells. At concentrations near the MIC, anthracimycin inhibited S. aureus nucleic acid synthesis as determined by optimized macromolecular synthesis methodology, with inhibition of DNA and RNA synthesis occurring in the absence of DNA intercalation. Anthracimycin at a single dose of 1 or 10 mg kg(-1) was able to protect mice from MRSA-induced mortality in a murine peritonitis model of infection. Anthracimycin provides an interesting new scaffold for future development of a novel MRSA antibiotic.

BACKGROUND: Infection with high-risk human papillomavirus (HR-HPV) may be higher in perinatally human immunodeficiency virus (HIV)-infected (PHIV) than HIV-uninfected (HU) adolescents because of long-standing immune deficiency. METHODS: PHIV and HU females aged 12-24 years in Thailand and Vietnam were matched by age group and lifetime sexual partners. At enrollment, blood, cervical, vaginal, anal, and oral samples were obtained for HPV-related testing. The Wilcoxon and Fisher exact tests were used for univariate and logistic regression for multivariate analyses. RESULTS: Ninety-three PHIV and 99 HU adolescents (median age 19 [18-20] years) were enrolled (June 2013-July 2015). Among PHIV, 94% were currently receiving antiretroviral therapy, median CD4 count was 593 (392-808) cells/mm3, and 62% had a viral load <40 copies/mL. Across anogenital compartments, PHIV had higher rates of any HPV detected (80% vs 60%; P = .003) and any HR-HPV (60% vs 43%, P = .02). Higher proportions of PHIV had abnormal Pap smears (eg, atypical squamous cells of unknown significance [ASC-US], 12% vs 14%; low-grade squamous intraepithelial neoplastic lesions, 19% vs 1%). After adjusting for ever being pregnant and asymptomatic sexually transmitted infections (STI) at enrollment, PHIV were more likely to have HR-HPV than HU (odds ratio, 2.02; 95% confidence interval, 1.09-3.77; P = .03). CONCLUSIONS: Perinatal HIV infection was associated with a higher risk of HR-HPV and abnormal cervical cytology. Our results underscore the need for HPV vaccination for PHIV adolescents and for prevention and screening programs for HPV and other STIs.