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A Rochalimaea-like organism (strain F9251) was isolated from a patient with endocarditis after blood drawn for culture before antimicrobial therapy was subcultured onto blood and chocolate agars and incubated for 2 weeks in 5% CO2. The strain was phenotypically similar to known Rochalimaea species. The cellular fatty acid composition of strain F9251 was close to but distinct from those of the three known Rochalimaea species and was most similar to that of R. vinsonii. Labeled DNA from strain F9251 was 59 to 67% related to DNAs from type strains of the three described Rochalimaea species, and its 16S rRNA gene sequence was 98.9%o or more homologous to their 16S rRNA gene sequences. These findings support classification of F9251 as a new Rochalimaea species, for which the name Rochalimaea elizabethae sp. nov. is proposed. The patient infected with the organism had large bacterial vegetations on his aortic valve and was cured with antibiotics and valve-replacement surgery. Recognition of the procedures required to identify this and other Rochalimaea species suggests that clinical laboratories should prolong the incubation times of cultures of blood and tissue from patients with suspected endocarditis, patients with fever of unknown origin, and immunocompromised patients with fever so that the full spectrum of disease caused by these organisms can be recognized.

CDC nonoxidizer group 2 (NO-2) currently consists of 15 gram-negative, rod-shaped, oxidase-negative, asaccharolytic, brown soluble pigment-producing strains isolated from blood cultures, usually from young adults. On the basis of their cellular fatty acid profiles, NO-2 strains formed a single group that was identical with the profile of Bordetella avium. 16S rRNA sequencing of one NO-2 strain and the type strains of B. pertussis, B. parapertussis, B. bronchiseptica, and B. avium showed a high degree of homology (Ն98% over 1,525 bases). The NO-2 guanine-plus-cytosine content (61.5 to 62.3 mol%) and major ubiquinone analysis (ubiquinone-8) results were both consistent with those for the genus Bordetella. DNA relatedness studies (hydroxyapatite method) confirmed a close relatedness between NO-2 and Bordetella species and demonstrated that NO-2 strains were a single new species. The name B. holmesii sp. nov. is proposed for CDC group NO-2. CDC nonoxidizer group 2 (NO-2) is the vernacular name given to gram-negative, nonoxidizing, brown soluble pigmentproducing rods sent for identification to the Special Bacteriology Reference Laboratory at the Centers for Disease Control and Prevention (CDC). The first of these strains was received in 1983. Since then, 14 additional strains have been received, all of which were isolated from blood cultures obtained, with few exceptions, from young adults. At least four of these strains were isolated from more than one blood culture per patient. Eleven NO-2 strains, including two isolates discovered outside the United States, have been received since 1989, raising the possibility that this group is an emerging pathogen. In this study we characterized the strains of NO-2 biochemically, by cellular fatty acid (CFA) and ubiquinone analysis, guanine-plus-cytosine (GϩC) content, 16S rRNA sequence analysis, and DNA-DNA hybridization. The results indicate that group NO-2 is a single, previously undescribed species whose closest relatives are in the genus Bordetella. We propose the name Bordetella holmesii for NO-2. MATERIALS AND METHODS Bacterial strains and culture conditions. The NO-2 strains and their sources are shown in Table 1. Bordetella pertussis ATCC 9797 T , Bordetella parapertussis ATCC 15311 T , Bordetella avium ATCC 35086 T , and Bordetella bronchiseptica ATCC 19395 T were obtained from the American Type Culture Collection, Rockville, Md. In addition, CFA profiles were determined for B. parapertussis F6288 and F6289, B. bronchiseptica B5821 and G1696, and B. pertussis 042, 083, and 087. The B. parapertussis and B. bronchiseptica strains were submitted to CDC as patient isolates and were identified by the Special Bacteriology Reference Laboratory. The B. pertussis strains were obtained from P. Cassiday, Pertussis Laboratory, Division of Bacterial and Mycotic Diseases, CDC. All strains were suspended in defibrinated rabbit blood and stored in a liquid nitrogen freezer until studied. Unless otherwise indicated, all strains except B. pertussis were grown on heart infusion agar with...

GenepsaA, which encodes the Streptococcus pneumoniae 37-kDa protein, was cloned in Escherichia coli, and its complete nucleotide sequence was determined. Analysis of the sequence of the 2.4-kb cloned fragment revealed three open reading frames (ORFs). ORF2, which is 933 bp long, was identified as psaA. The two other ORFs identified flankpsaA. ORF1, located upstream ofpsaA, is 836 nucleotides long and encodes a protein with a calculated molecular mass of 29,843 Da. The sequence for ORF3, located downstream of psaA, was only partially determined. Northern (RNA) blot analysis of pneumococcal RNA suggests that psaA4 is transcribed as part of a polycistronic message. Analysis of the primary structure of the protein encoded by this gene indicated significant similarity to two previously reported streptococcal proteins, SsaB (80%o similarity) and FimA (92.3% similarity), from S. sanguis and S. parasanguis, respectively. These two homologous proteins have been shown to be associated with bacterial adhesion, and the possibility of a similar role for PsaA is hypothesized.

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The streptococcal C5a peptidase removes a six-amino-acid fragment from human C5a and thereby inactivates this chemotaxin. We used transposon and chemical mutagenesis to generate mutants of Streptococcus pyogenes that did not produce C5a peptidase. These mutants showed no alteration in expression of capsule, M protein, streptolysins O and S, or pyrogenic exotoxin C. Serial passage of a peptidase-producing strain in vivo resulted in a 100-fold increase in production of C5a peptidase. The presence of C5a peptidase delayed the accumulation of polymorphonuclear leukocytes (PMNLs) in the peritoneal cavities of mice after intraperitoneal challenge. However, there was no difference in virulence (as evaluated by LD50) between strains that produced and those that lacked C5a peptidase. Although C5a peptidase is expressed on the cell surface, antibody to this enzyme did not opsonize streptococci for phagocytosis in vitro. These studies show that C5a peptidase alters the normal host inflammatory response by delaying the accumulation of PMNLs at the foci of streptococcal infection.

Arbitrarily primed polymerase chain reaction (AP-PCR) was used to characterize LegioneUa pneumophila serogroup 1. Cells from a single colony could be subtyped by AP-PCR within a few hours. The discrimination between strains of L. pneumophila serogroup 1 by AP-PCR was equivalent to that by monoclonal antibody analysis and ribotyping. Four strains representing the monoclonal antibody pattern most frequently associated

A new slowly growing nonphotochromogenic Mycobacterium species of clinical importance is described. The biochemical characteristics of this organism were similar to those of Mycobacterium xenopi and members of the Mycohcterium avium complex. However, none of the strains reacted with commercially available genetic probes for the M. avium complex. The strains were resistant to most antituberculosis drugs. Multilocus enzyme electrophoresis revealed two original electrophoretic types, which was suggestive of new species. The strains contained a-, keto-, and dicarboxylic mycolates, as determined by thin-layer chromatography. A mycolic acid analysis by high-performance liquid chromatography revealed a chromatographic pattern similar to that of M. xenopi, but distinct from the patterns of previously described Mycobacterium species. Hexadecanoic and tuberculostearic acids were identified as the major cell wall fatty acids by gas-liquid chromatographic analysis; hexacosanoic acid was the major mycolic acid cleavage product, and 2-eicosanol was the major alcohol. Unusual strains not considered typical of previously described Mycobacterium species were received from the Veterans Administration Laboratory, West Haven, Conn. These organisms were patient isolates obtained from diverse geographic locations in the United States. Subsequently, additional strains were collected and characterized at the Centers for Disease Control, and the results corroborated the results of a previous study performed with high-performance liquid chromatography (HPLC) which identified them as members of a new Mycobactenurn species (2). The isolation of these bacteria from clinical specimens may pose a problem since they are resistant in vitro to most of the commonly used antituberculosis drugs. The strains were extensively characterized and found to be unique. The new species is named Mycobacteriurn celatum. MATERIALS AND METHODSStrains of mycobacteria. The sources of the strains, their designations, and their geographic distribution are shown in Table 1.Growth temperatures, colonial and cellular features, and biochemical tests. Single-colony isolates of each strain were selected by using a magnification of x10 and tested for purity. After each separate colonial isolate was grown in Middlebrook-Cohn 7H9 liquid medium, agar plates containing Middlebrook-Cohn 7H10 medium (7H10 medium) were streaked, and the growth was examined visually for purity. In addition, individual colony isolates were examined by performing an HPLC analysis of mycolic acids to verify the unique chromatographic patterns (2). The growth of the strains was examined on Lliwenstein-Jensen (L-J) egg medium and 7H10 medium incubated at 27, 30, 33, 37, 42, and 45°C. Morphologic variation in colonies was determined by examining L-J medium cultures incubated at 37°C. Pigmen-* Corresponding author. tation and photoinduction of pigment production were determined on 7H10 agar incubated at 37°C. Cell morphology was determined by microscopic examination (magnification, ~1 , 0 0 0 ) of colon...