WU and KI polyomavirus infections are widespread.

Here, we report the sequencing and classification of Nyamanini virus (NYMV) and Midway virus (MIDWV), two antigenically related viruses that were first isolated in 1957 and 1966, respectively. Although these viruses have been cultured multiple times from cattle egrets, seabirds, and their ticks, efforts to classify them taxonomically using conventional serological and electron microscopic approaches have failed completely. We used a random shotgun sequencing strategy to define the genomes of NYMV and MIDWV. Contigs of 11,631 and 11,752 nucleotides, representing the complete genome of NYMV and the near-complete genome of MIDWV, respectively, were assembled. Each virus genome was predicted to carry six open reading frames (ORFs). BLAST analysis indicated that only two of the ORF proteins of each virus, the putative nucleocapsid and polymerase, had detectable sequence similarity to known viral proteins. Phylogenetic analysis of these ORF proteins demonstrated that the closest relatives of NYNV and MIDWV are negative-stranded-RNA viruses in the order Mononegavirales. On the basis of their very limited sequence similarity to known viruses, we propose that NYMV and MIDWV define a novel genus, Nyavirus, in this order.Nyamanini virus (NYMV) was first isolated in 1957 from a cattle egret (Bubulcus ibis) in South Africa (24). It has subsequently been isolated in Nigeria, Egypt, India, and Thailand from cattle egrets and Argas walkerae ticks (14,16,24). Although there has been no recognized human infection or disease associated with NYMV, suckling mice succumbed to NYMV infection 7 or 8 days after intracerebral inoculation (14). NYMV has not been definitively characterized or classified to date (10).Midway virus (MIDWV) was first isolated in 1966 from seabird ticks of two species [Ornithodoros (Alectorobius) spp.] collected on the Midway, Kure, and Manana islands in the Central Pacific and from northern Honshu, Japan. In addition, on Aomatsushima Island, nestling seabirds of two seabird species, Larus crassirostris and Nycticorax nycticorax, were found to have antibody to MIDWV. This virus is pathogenic for newborn Swiss mice but not 4-week-old Swiss mice injected intracranially. Also, the virus is cytopathic in BHK-21 cells and produces plaques in Vero cells. Efforts to classify MIDWV have revealed only that MIDWV is antigenically related to NYMV in cross-box complement fixation (CF) assays (22).To date, conventional approaches, such as serological analysis and electron microscopy (EM), have not yielded definitive characterization of MIDWV or NYMV. Heretofore, it was not known whether MIDWV and NYMV are DNA viruses or RNA viruses or to which virus family they belong. In this paper, we describe the application of unbiased high-throughput sequencing to define the genome sequences of NYMV and MIDWV. By analysis of their genomes, NYMV and MIDWV were determined to be negative-stranded RNA viruses highly divergent from all known viruses but most closely related to viruses in the order Mononegavirales. On the basis of the analys...

Assembly of many spherical virus capsids is guided by an internal scaffolding protein or group of proteins that are often cleaved and eliminated in connection with maturation and incorporation of the genome. In cytomegalovirus there are at least two proteins that contribute to this scaffolding function; one is the maturational protease precursor (pUL80a), and the other is the assembly protein precursor (pUL80.5) encoded by a shorter genetic element within UL80a. Yeast GAL4 two-hybrid assays established that both proteins contain a carboxyl-conserved domain that is required for their interaction with the major capsid protein (pUL86) and an amino-conserved domain (ACD) that is required for their self-interaction and for their interaction with each other. In the work reported here, we demonstrate that when the ACD is deleted (␦ACD) or disrupted by a point mutation (L47A), the bacterially expressed mutant protein sediments as a monomer during rate-velocity centrifugation, whereas the wild-type protein sediments mainly as oligomers. We also show that the L47A mutation reduces the production of infectious virus by at least 90%, results in the formation of irregular nuclear capsids, gives rise to tube-like structures in the nucleus that resemble the capsid core in cross-section and contain UL80 proteins, slows nuclear translocation of the major capsid protein, and may slow cleavage by the maturational protease. We provide physical corroboration that mutating the ACD disrupts self-interaction of the UL80 proteins and biological support for the proposal that the ACD has a critical role in capsid assembly and production of infectious virus.A common feature among viruses with a spherical capsid is their use of a transient internal scaffolding structure to coordinate assembly of the capsid shell (7,11,13,17,32). Among the herpes group viruses this scaffold is made up of at least two essential proteins. These are encoded by UL80a and UL80.5 in human cytomegalovirus (HCMV) (17,38,39) and have counterparts in the other herpesviruses (12,22,36,39). UL80a, the longer of the two CMV open reading frames (ORFs), specifies the 74-kDa viral maturational protease precursor (pPR), and contains genes for three additional independently synthesized proteins. All four are in frame and carboxy coterminal, such that the amino acid sequence of the smaller proteins is identical to the sequence of the carboxyl end of the larger proteins (22, 39), as illustrated in Fig. 1. UL80.5 specifies the most abundant of the UL80 proteins, which is called the assembly protein precursor (pAP) and is the core component of the scaffold.The requirement for these proteins during capsid formation and maturation has been demonstrated by using mutant viruses (10, 15, 29, 41) and a recombinant-baculovirus herpes simplex virus (HSV) capsid assembly system (33, 34). In the absence of a pAP homolog (i.e., HSV pUL26.5 or preVP22a), the formation of closed spherical capsids is disrupted, and aberrantly shaped particles accumulate in the nucleus without forming infectiou...

f Cache Valley virus was initially isolated from mosquitoes and had been linked to central nervous system-associated diseases. A case of Cache Valley virus infection is described. The virus was cultured from a patient's cerebrospinal fluid and identified with real-time reverse transcription-PCR and sequencing, which also yielded the complete viral coding sequences. CASE REPORT In mid-September 2011, a 63-year-old woman presented to an upstate New York hospital with complaints of fever, headache, neck stiffness, and photophobia. One week earlier, she had noticed a macular, nonpruritic lesion on her right forearm, about 3 cm in diameter, with central clearing. Three days prior, as the first lesion was fading, a petechial rash developed on her lower extremities that spread to her torso. She then traveled to Pennsylvania for a weekend, and during this time she developed the mentioned fever and symptoms of meningitis. She returned home and went to the Emergency Department (ED) of the hospital the next morning.On physical examination, the patient appeared alert and oriented, with a blood pressure of 148-mm/80-mm Hg, a pulse rate of 87 per min, a respiratory rate of 18 per min, an oral temperature of 37.6°C, and an oxygen saturation of 99% on room air. She had a scattered, bilateral, petechial rash on her thighs; meanwhile, the lesions on her back and abdomen were fading. She had moderate neck stiffness. Her neurologic exam was otherwise normal; there was no evidence of encephalitis, cranial nerve abnormalities, or focal findings.Her medical record included a history of hypertension, hypothyroidism, meningioma, and migraine headaches and of rheumatic fever during childhood. The patient stated that she and her husband frequently camped outdoors. Throughout mid-to late August they camped in Wyoming and Livingston counties in New York state and also embarked on a 5-day camping trip in Dansville, NY, through Vermont and New Hampshire. She lived with her husband, had a cat, and frequently tended to her garden around her home. She had no knowledge of any sick contact.Her white blood cell count on presentation was 5,700/l, with a normal differential. Hematocrit was normal at 42%, and platelets were normal at 212,000/l. Computed tomography of the head without contrast showed mild atrophy without evidence of acute intracranial abnormality. Blood cultures were drawn, and she was sent home on doxycycline. The patient returned to the ED the following day with new complaints of nausea and vomiting in addition to the previously reported symptoms.The patient was admitted to the hospital with a preliminary diagnosis of aseptic meningitis. A lumbar puncture was performed, and the cerebrospinal fluid (CSF) showed 216 nucleated cells, with 91% lymphocytes, 7% monocytes, 1% basophils, and 1% polymorphonuclear cells. CSF chemistries were normal, with a glucose concentration of 60 mg/dl (56% of the serum level) and protein of 46 mg/dl. No microorganism was seen in the CSF by Gram stain. Magnetic resonance imaging of the brain showed only a ...