Global mRNA decay analysis at single nucleotide resolution reveals segmental and positional degradation patterns in a Gram-positive bacterium

Table 1 General features of the Bacillus cereus transcriptome, for strains ATCC 10987 and ATCC 14579

	B. cereus ATCC 10987	B. cereus ATCC 14579
Annotated genes	6,014	5,497
Expressed genes	3,685	2,061
Operons	2,271	1,696
Genes with mRNA half-lives determined	2,745	1,675
TSS determined	1,222	1,002
Median 5' UTR length (nucleotides)	74.5	59
TES determined	918	717
Median 3' UTR length	31	27
Transcribed units with no annotation	20	17
Median gene half-life (minutes)	2.4	2.6
Minimum gene half-life (minutes)	0.6	0.6
Maximum gene half-life (minutes)	15 or above	15 or above
Median gene expression level (RPKM)	44.1	109
Minimum gene expression level (RPKM)	5.2	20.3
Maximum gene expression level (RPKM)	4 × 10⁴	4 × 10⁴

The criterion used for 'expressed genes' was having an expression level higher than 50 RPK in the t0 sample. The criterion used for 'operons' was a continuous stretch of overlapping reads covering one to several genes with the same orientation in the genome and for which the average sequence coverage was higher than five reads per base pair. RPKM, reads per kilobase per megabase.

ISSN: 1474-760X