Spirilla (sing. spirillum) shapes are curved-shaped bacteria which can range from a gently curved shape to a corkscrew spiral. Many spirilla are rigid and able to move. The length of rod-shaped bacteria is over 2–100 μm. Spiral-shaped bacteria occur in one of three forms: vibrio, spirillum, and spirochete (Fig. 7.1 c): (i) Vibrio.

2022年8月10日 · Spirilla (or spirillum for a single cell) are curved bacteria which can range from a gently curved shape to a corkscrew-like spiral. Many spirilla are rigid and capable of movement. A special group of spirilla known as spirochetes are long, slender, and flexible.

The gram-positive cocci are a large group of bacteria with similar morphology. All are spherical or nearly so, but they vary considerably in size. Members of some genera are identifiable by the way cells are attached to one another: in pockets, in chains, or grape-like clusters.

Spirilla (singular, Spirillum) are a group of bacteria characterized by a corkscrew (spiral) appearance. They are Gram-negative bacteria and are characterized by motile structures known as flagella. With the exception of one species, members of this group are commonly found in aquatic habitats where they are capable of swimming rapidly.

2023年9月7日 · Gram-positive bacteria are a group of microorganisms that have a thick peptidoglycan cell wall, which allows them to retain a crystal violet stain during the Gram stain protocol. They can be found in a variety of environments and can be harmless or pathogenic to humans and other organisms.

Direct examination showed gram-positive spiral coiled rod bacilli (Fig. 1 ), which was confirmed by scanning electron microscopy (Fig. 2 B and C) [2]. The blood culture was immediately analyzed by 16S rRNA sequencing [3], and the 935-bp amplicon generated shared 99.3% identity with Clostridium saccharogumia NR_043,550. Fig. 1.

Spirilla, also known as spirillum bacteria, are a type of bacteria that have a helical or spiral shape. They belong to the group of bacteria called spirilla, which also includes vibrios. Spirilla can be found in a variety of environments, including freshwater, marine water, and soil.

Characterization of capsules and the formation of extracellular vesicles by Gram-positive bacteria close the section on cell envelopes which have a high impact on bacterial pathogenesis. In addition, the specialized complex and unusual cell wall of mycobacteria is introduced thereafter.

Swollen pleomorphic forms are common, actively motile by means of a single polar flagellum, strict anaerobes which reduce sulphates to hydrogen sulphide. Species assigned to the genus Caulobacter are aquatic, oligotrophic, aerobic, freshwater, Gram-negative Alphaproteobacteria.

Hylemon et al. (1973b) divided the genus into the three genera Spirillum, Aquaspirillum, and Oceanospirillum on the basis of their DNA base composition and certain physiological characteristics.