The Anaerobic Gram-Positive Cocci
- PDF / 401,115 Bytes
- 14 Pages / 539 x 751 pts Page_size
- 33 Downloads / 206 Views
CHAPTER 1.2.26 ehT
c i boreanA
ev i t i soP-marG
The Anaerobic Gram-Positive Cocci TAKAYUKI EZAKI, NA LI AND YOSHIAKI KAWAMURA
Introduction The anaerobic Gram-positive cocci (also known as peptococci and peptostreptococci) discussed in this chapter are limited to firmicutes with low mol% G+C. They are Peptococcus, Peptostreptococcus, Anaerococcus, Peptoniphilus, Gallicola, Finegoldia, Micromonas, Ruminococcus, Coprococcus and Sarcina. All except Anaerococcus, Peptoniphilus, Gallicola, Finegoldia and Micromonas belong to the classical family Peptococaceae (Rogosa, 1974). During the last 10 years, many members of the old genus Peptostreptococcus were transferred to many other genera. Most anaerobic Gram-positive cocci belong to the normal flora of the human gastrointestinal tract, vagina and oral cavity and often are found in human clinical specimens (Brook and Frazier, 1990; Ezaki et al., 1992). (Most human clinical isolates were identified as peptostreptococci.) Phylogenetically, anaerobic Gram-positive cocci belong to the phylum Clostridium. Indeed, based on 16S rRNA sequences, all species of the genus Peptostreptococcus (Li et al., 1994; Collins et al., 1994) were in different groups in this phylum. Peptococcus niger was close to the clostridial cluster III (Collins et al., 1994). Sarcina ventriculi was close to the clostridial cluster I (Li et al., 1994; Willems and Collins, 1994), and the ruminococci and coprococci were within clostridial cluster XIV (Willems and Collins, 1995; Rainey and Janssen, 1995). Members of the genus Peptostreptococcus also were clustered into three groups within the phylum Clostridium: P. anaerobius within clostridial cluster XI, “P. heliotrinreducens,” recently transferred to a new genus Slackia (a high mol% G+C firmicute; Wade et al., 1999), and the remaining species classified with clostridial cluster XIII. Accumulated chemotaxonomic data also proved that peptostreptococci were in different groups. Old peptostreptococci have several peptidoglycan structures and their structures differ from that of the type species, P. anaerobius (Li et al., 1992; Murdoch et al., 1997). Using these data, peptostreptococci were recently reclassi-
fied into five genera: Anaerococcus, Peptoniphilus, Finegoldia, Micromonas and Gallicola.
Habitat Anaerobic cocci are part of the normal flora of the human oral cavity, alimentary tract, skin and vagina (Moore and Holdeman, 1974; Holdeman et al., 1986; Tanner and Stillmann, 1993). Among them, Micromonas micros and Finegoldia magna often are isolated from sites of oral infection and otorrhea (Shah and Gharbia, 1995). Sarcinae are isolated from soil but also from the digestive tract of humans and animals (Canale-Parola, 1970; Canale-Parola, 1986). The anaerococci, peptoniphili, peptostreptococci, finegoldiae and micromonades are found in the mouth and upper respiratory tract and in the lower small intestine, colon and vagina (Finegold and George, 1989; Murdoch, 1998; Tanner and Stillmann, 1993). Ruminococcus obeum and R. bromii are often isolated from the large inte
Data Loading...
