Biomaterial Database

Polynucleotide phosphorylase-deficient mutants of Pseudomonas putida. 2003

Rebecca Favaro, and Gianni Dehò

Dipartimento di Genetica e di Biologia dei Microrganismi, Università degli Studi di Milano, Via Celoria 26, 20133 Milan, Italy.

In bacteria, polynucleotide phosphorylase (PNPase) is one of the main exonucleolytic activities involved in RNA turnover and is widely conserved. In spite of this, PNPase does not seem to be essential for growth if the organisms are not subjected to special conditions, such as low temperature. We identified the PNPase-encoding gene (pnp) of Pseudomonas putida and constructed deletion mutants that did not exhibit cold sensitivity. In addition, we found that the transcription pattern of pnp upon cold shock in P. putida was markedly different from that in Escherichia coli. It thus appears that pnp expression control and the physiological roles in the cold may be different in different bacterial species.

UI	MeSH Term	Description	Entries
D011117	Polyribonucleotide Nucleotidyltransferase	An enzyme of the transferase class that catalyzes the reaction RNA(n+1) and orthophosphate to yield RNA(n) and a nucleoside diphosphate, or the reverse reaction. ADP, IDP, GDP, UDP, and CDP can act as donors in the latter case. (From Dorland, 27th ed) EC 2.7.7.8.	Polynucleotide Phosphorylase,Nucleotidyltransferase, Polyribonucleotide,Phosphorylase, Polynucleotide
D003080	Cold Temperature	An absence of warmth or heat or a temperature notably below an accustomed norm.	Cold,Cold Temperatures,Temperature, Cold,Temperatures, Cold
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D012269	Ribosomal Proteins	Proteins found in ribosomes. They are believed to have a catalytic function in reconstituting biologically active ribosomal subunits.	Proteins, Ribosomal,Ribosomal Protein,Protein, Ribosomal
D014158	Transcription, Genetic	The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.	Genetic Transcription
D015964	Gene Expression Regulation, Bacterial	Any of the processes by which cytoplasmic or intercellular factors influence the differential control of gene action in bacteria.	Bacterial Gene Expression Regulation,Regulation of Gene Expression, Bacterial,Regulation, Gene Expression, Bacterial
D016958	Pseudomonas putida	A species of gram-negative, aerobic bacteria isolated from soil and water as well as clinical specimens. Occasionally it is an opportunistic pathogen.
D017353	Gene Deletion	A genetic rearrangement through loss of segments of DNA or RNA, bringing sequences which are normally separated into close proximity. This deletion may be detected using cytogenetic techniques and can also be inferred from the phenotype, indicating a deletion at one specific locus.	Deletion, Gene,Deletions, Gene,Gene Deletions
D018869	Heat-Shock Response	A sequence of responses that occur when an organism is exposed to excessive heat. In humans, an increase in skin temperature triggers muscle relaxation, sweating, and vasodilation.	Heat-Shock Reaction,Heat Shock,Heat Shock Stress,Heat Stress,Heat-Stress Reaction,Heat-Stress Response,Heat Shock Reaction,Heat Shock Response,Heat Shock Stresses,Heat Shocks,Heat Stress Reaction,Heat Stress Response,Heat Stresses,Heat-Shock Reactions,Heat-Shock Responses,Heat-Stress Reactions,Heat-Stress Responses,Shock, Heat,Stress, Heat,Stress, Heat Shock