In spite of only weak sequence similarity, the operon was equivalent www.selleckchem.com/products/Bortezomib.html to the bldK operon of Streptomyces coelicolor A3(2) in terms

of chromosomal location and function. Transcription of the operon appeared not to be directly regulated by AdpA, a global regulator of morphological and physiological development in S. griseus, although it was affected by adpA inactivation. This study revealed that an ABC transporter was essential for aerial mycelium formation not only in S. coelicolor A3(2) but also in S. griseus, indicating that extracellular signaling by certain peptides should be conserved among different Streptomyces species. Members of the Gram-positive, soil-dwelling, filamentous bacterial genus Streptomyces undergo a complex process of morphological differentiation during their life cycle.

Spores germinate to form a branched, multinucleoid substrate mycelium, which then gives rise to an aerial mycelium. After septa have been formed at regular intervals along the aerial hyphae, long chains of uninucleoid spores are produced. Because of their complex morphogenesis, Streptomyces spp. have become model prokaryotes for the study of multicellular differentiation. A number of genes that are required for aerial mycelium formation have been identified in Streptomyces coelicolor A3(2), many of which have been given a bld (bald) designation (Table 1) because the mutants lack the characteristic fuzzy colony morphology of the wild-type (WT) organism (Kelemen & Buttner, 1998; Chater & Horinouchi, 2003; Claessen Luminespib cell line et al., 2006). A hierarchical extracellular signaling cascade has been proposed based on the ability of some bld mutants

to partially restore aerial mycelium formation in other bld mutants when the two are grown in close proximity (Willey et al., 1991, 1993; Nodwell et al., 1999). Because of this ‘extracellular complementation,’ it has been proposed that buy Abiraterone each bld gene is involved, directly or indirectly, in the synthesis of, perception of, or response to a different extracellular signaling molecule. However, almost all of the extracellular signaling molecules have not been identified and an increasing number of questions to the old view of the straightforward hierarchical extracellular signaling cascade have been raised. In fact, a direct involvement in the extracellular signaling molecule has been shown only in bldK, a gene cluster that encodes the components of an oligopeptide permease family of the ATP-binding cassette (ABC) transporter. A 655 Da oligopeptide that is imported by the BldK transporter has been identified, but its precise amino acid sequence is yet to be determined (Nodwell & Losick, 1998). The initiation of aerial mycelium formation in another Streptomyces species, Streptomyces griseus, has also been characterized extensively. In S.

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“We examined the response characteristics of primary auditory cortex (A1) neurons in adult cats partially but extensively deafened by ototoxic drugs 2–8 days after birth. The damage evoked extensive A1 topographic map reorganization as also found by others, but a novel finding was that in the majority of cats

with low-frequency edges to the cochlear lesion, the area of reorganization segregated into two areas expressing the same novel frequency inputs but differentiated by neuronal sensitivity and responsiveness. Immediately adjacent to normal A1 is an approximately 1.2-mm-wide area of reorganization in which sensitivity and responsiveness to sound are similar to that in normal A1 in the same animals and in unlesioned adult animals. Extending further into deprived A1 is a more extensive area of reorganization where neurons have poorer sensitivity and responsiveness to new inputs. These two

areas did not differ http://www.selleckchem.com/products/MLN-2238.html in response-area bandwidth and response latency. We interpret these novel changes as the cortical consequences of severe receptor organ lesions extending to low-frequency cochlear regions. We speculate that the two areas of A1 reorganization this website may reflect differences in the transcortical spatial distribution of thalamo-cortical and horizontal intracortical connections. Qualitatively similar changes in response properties have been seen after retinal lesions producing large areas of visual cortical reorganization, suggesting they might be a general consequence of receptor lesions that deprive large regions of cortex of normal input. These effects may have perceptual implications for the use of cochlear implants in patients with residual low-frequency hearing. “
“Expression of the immediate-early gene c-fos was used to test for different patterns of temporal

lobe interactions when rats explore either novel or familiar objects. A new behavioural test of recognition memory was first devised to generate robust levels of novelty discrimination and to provide a matched control condition using familiar objects. Increased c-Fos activity was found in caudal but not rostral portions of the perirhinal cortex (areas 35/36) and in area Te2 in rats showing object DNA Synthesis inhibitor recognition, i.e. preferential exploration of novel vs. familiar objects. The findings are presented at a higher anatomical resolution than previous studies of immediate-early gene expression and object novelty and, crucially, provide the first analyses when animals are actively discriminating the novel objects. Novel vs. familiar object comparisons also revealed altered c-Fos patterns in hippocampal subfields, with relative increases in CA3 and CA1 and decreases in the dentate gyrus. These hippocampal changes match those previously reported for the automatic coding of object–spatial associations.

Publication in HIV Medicine. Shortened version detailing concise summary of recommendations. E-learning module accredited for CME. Educational Selleck Alvelestat slide set to support local and regional educational meetings. National BHIVA audit programme. The guidelines will be next fully updated and revised in 2014. However, the Writing Group will continue to meet regularly to consider new information from high-quality studies and publish amendments and addendums to the current recommendations before the full revision date where this is thought to be clinically important to ensure

continued best clinical practice. “
“Deinococcus radiodurans tolerates extensive DNA damage and exhibits differential expression of various genes associated with the growth of the organism selleck compound and DNA repair. In cells treated with γ radiation, the levels of cyclic AMP (cAMP) and ATP increased rapidly by differentially regulating adenylyl cyclase (AC) and 2′3′ cAMP phosphodiesterase. The levels of cAMP, ATP, AC and protein kinases were high when phosphodiesterase activity was low. These cells exhibited in vivo inhibition of nucleolytic function by reversible protein phosphorylation and contained the comparatively higher levels of total phosphoproteins. We suggest that Deinococcus, a prokaryote, uses DNA damage-induced signaling mechanism as evidenced by γ radiation-induced synthesis

of secondary messengers and signaling enzymes. Protein phosphorylation constitutes an important regulatory network that controls the cellular functions including cell division, cellular differentiation and signal transduction in all organisms (Pawson, 1994). At molecular levels, this regulates metabolic functions such as enzyme activity modulation, protein trafficking, protein–protein and DNA–protein interactions and recycling of proteins (Ubersax & Ferrell, 2007). By reversible protein phosphorylation, the functions of proteins can be rapidly modulated without the need for new protein synthesis

or degradation. This phenomenon Farnesyltransferase is regulated by the relative abundance of stress-responsive protein kinases and phosphatases in the cells (Sefton & Hunter, 1998). In eukaryotes, the significance of reversible protein phosphorylation is amply illustrated by the involvement of DNA damage-induced signal transduction and protein kinase C-mediated signaling mechanism in cell cycle regulation (Sancar et al., 2004; Kitagawa & Kastan, 2005). The existence of such mechanisms and their implications in DNA strand break (DSB) repair and bacterial growth would be worth investigating in Deinococcus radiodurans, a bacterium that confers extraordinary tolerance to DNA damage and has acquired a large number of putative sensor kinases and response regulators (White et al., 1999) from other organisms (Makarova et al., 2001).

, 2003). Expression of ropB in the acpXL mutant was decreased by approximately 14-fold compared with ropB expression in the wild-type strain (Table 2). This is not as dramatic as the reduction in ropB expression in a fabF2XL, fabF1XL mutant, where expression is reduced by approximately 82-fold in agreement with previous observations of ropB down-regulation in a fabF2XL, fabF1XL mutant (Foreman et al., 2010). Based on comparison with levels in a negative control gusA vector, ropB is essentially not expressed in the fabF2XL, fabF1XL mutant, while AZD2014 cell line there

is still a low level of expression in the acpXL mutant. Mutants of acpXL, fabF2XL, fabF1XL, and ropB are all reported to have similar sensitivities to membrane stressors (Vedam et al., 2003; Vanderlinde et al., 2009; Foreman et al., 2010). Given the similarity in phenotypes and the significant down-regulation of ropB in the fabXL mutants, we tested the hypothesis that ropB down-regulation contributes to the this website detergent, hyperosmotic, and acid sensitivity phenotypes. Constitutive ropB expression partially restored growth of the mutants in the presence of the bile acid deoxycholate and the detergent sarcosyl (Fig. 2). Constitutive expression of ropB fully restored growth of the fabXL mutants in both hyperosmotic and acidic pH growth conditions (Fig. 2). In addition to the phenotypes described previously, the

fabF2XL, fabF1XL mutant is unable to grow on the solid complex medium, TY (Vanderlinde et al., 2009). Constitutive ropB

expression did not rescue growth of the fabF2XL, fabF1XL mutant on TY (data not shown). A fabF2XL, fabF1XL, ropB double mutant had phenotypes similar to the fabF2XL, fabF1XL single mutant (data not shown). Notably, the phenotypes described previously 3-oxoacyl-(acyl-carrier-protein) reductase for the fabXL mutants can be complemented by providing the intact fabXL genes, in trans (Vedam et al., 2003; Vanderlinde et al., 2009). We used a chromosomal ropB::gusA fusion to determine whether complementation of the acpXL mutation also restored expression of ropB. Average expression (± SD) of the chromosomal fusion in the acpXL mutant was 835 ± 47.2 Miller units, whereas gusA activity in the wild-type and acpXL complemented strains was 7367 ± 953 Miller units and 5344 ± 128 Miller units, respectively. The difference in mean expression of ropB in the acpXL mutant compared with the wild-type and acpXL complement was statistically significant based on one-way anova with Tukey’s post hoc analysis, P value < 0.001. Although the rhizobial cell envelope has been extensively characterized, there is a paucity of data regarding how the different components interact. Furthermore, identifying and characterizing epistatic interactions between bacterial cell envelope components is critical to understanding envelope biogenesis. The identified genetic regulatory link between the outer membrane protein gene, ropB, and the VLCFA component of the lipid A in R.

Kornacki, unpublished data) were gifts of Jon Kornacki. pJAK17, which is identical to pJAK16, except for the orientation of its MCS, is derived from pMMB67HE (Fürste et al., 1986) and is described in Thomson et al. (1999). A DNA fragment with the aadA gene (Spr), originally from plasmid R100-1 [a derivative of plasmid R100 (Acc. no. AP000342; Hirota et al., 1964)], was amplified by PCR

from pJH019, which is pUC19-aadA. A DNA fragment with the LBH589 in vivo aacC1 gene (Gmr) (Acc. no. P23181) was amplified by PCR from pKX11, which is pBBR1MCS-aacC1. A DNA fragment with the IncP oriT region, originally derived from plasmid RK2 (Acc. no. L27758), was amplified from pAA56, which is pUC19-USSAa-oriTIncP. The HRs, GSI-IX in vitro which were 200–282 bp in size, were targeted to pACYC177, the pJAK12/14/16 series, and pSIM9, as described in ‘Results and discussion’. Oligonucleotide primers for PCR and nucleotide sequencing were purchased from Sigma-Aldrich. The nucleotide sequences for the PCR primers are listed in Table 2. Luria–Bertani

(LB) medium (Sambrook et al., 1989) was used for bacterial growth. SOC medium (Hanahan, 1983; Invitrogen) was used to express cells after transformation or recombineering. Antibiotics were used at the following concentrations (in μg mL−1): chloramphenicol, 50; gentamicin, 10; kanamycin, 50; nalidixic acid, 20; penicillin, 150; and spectinomycin, 50. X-Gal Dolichyl-phosphate-mannose-protein mannosyltransferase (5-bromo-4-chloro-3-indolyl-β-d-galactopyranoside) was used at 40 μg mL−1; IPTG (isopropyl β-d-thiogalactopyranoside), at 1 mM. Restriction endonucleases and T4 DNA ligase were purchased from New England Biolabs; Taq DNA polymerase, from Thermo Scientific. The enzymes were used as recommended by the supplier.

PCR amplification of DNA (Saiki et al., 1988), agarose gel electrophoresis (Maniatis et al., 1982), transformation (Cohen et al., 1972), and recombineering (Sharan et al., 2009) have been described. Plasmid DNA was prepared with Plasmid Mini Kits (Qiagen), and purification of DNA fragments was performed with PureLink PCR Purification Kits (Invitrogen). All plasmids were confirmed by nucleotide sequencing (GeneWiz). The scheme for the strategy is shown in Fig. 1. Any plasmid can be used to make the recombineering template. We often use pCR2.1 TOPO for the template plasmid because its TA-cloning site and flanking restriction endonuclease cleavage sites are convenient. To clone a segment, any two restriction endonucleases that generate noncompatible ends can be used. The constructs reported here linked 3 or 4 DNA segments into a recombineering template, two of which in each were HRs that could recombine with the target sequence. Theoretically, any number of segments can be linked. The number of different restriction endonucleases needed is n + 1, where n is the number of segments to be cloned. The requirements for the method are simple and few.

At the first study visit in AMP, clinical information was collected including age, sex, race, Tanner stage (by physical examination), and family history of diabetes, atherosclerosis, myocardial Autophagy inhibitor infarction and hyperlipidaemia. Weight and height were measured and BMI was calculated [weight (kg)/height2 (m2)] and expressed as z-scores [24]. Waist and hip circumferences were measured with a nonstretchable plastic tape measure according to standard methods [25]. Anthropometric measures were standardized at the annual PHACS meeting through training sessions conducted by a registered dietician who was experienced in anthropometry. The per cent

body fat was calculated from a total body dual-energy X-ray absorptiometry (DXA) scan performed on either a Lunar (General Electric Healthcare, Bucks, UK) or Hologic (Hologic Inc., Bedford,

MA) scanner according to standard methods [26]. Scans were sent to the Body Composition Analysis Center at Tufts University School of Medicine (Boston, MA, USA) for central analysis and standardization. Fasting serum levels of total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides, glucose and insulin were measured locally and in real-time at study entry for all HIV-infected children. Non-HDL cholesterol was calculated as the difference between total and HDL cholesterol. In HEU children, Fostamatinib plasma lipid and lipoproteins were measured by standard methods at the Diabetes Research Institute Clinical Chemistry Laboratory at the University of Miami (Miami, FL), on a Cobas 6000 analyser (Roche Diagnostics, Indianapolis, IN) Florfenicol using the manufacturer’s reagents and procedures. The

homeostatic model assessment of insulin resistance (HOMA-IR) score was calculated: [fasting insulin (μU/mL) × fasting glucose (mmol/L)]/22.5 [27]. For HIV-infected children only, concurrent Centers for Disease Control and Prevention (CDC) paediatric HIV disease stage [28], absolute CD4 T-lymphocyte cell count, plasma HIV-1 RNA by quantitative polymerase chain reaction (PCR) (viral load) and ARV regimens were recorded. Fibrinogen and CRP were measured at a central laboratory by nephelometry on a Dade-Behring (Deerfield, IL) auto-analyser using the manufacturer’s reagents and instructions. Intra- and interassay coefficients of variation were 2.6 and 2.7%, respectively, for fibrinogen and 4.4 and 5.7%, respectively, for CRP. Adiponectin was measured using a double-antibody radioimmunoassay (Linco Research, St Charles, MO), with intra- and inter-assay coefficients of variation both <5%. CRP values >10 mg/dL were not used in the data analysis because high levels could be caused by intercurrent infection.

At the first study visit in AMP, clinical information was collected including age, sex, race, Tanner stage (by physical examination), and family history of diabetes, atherosclerosis, myocardial http://www.selleckchem.com/products/azd6738.html infarction and hyperlipidaemia. Weight and height were measured and BMI was calculated [weight (kg)/height2 (m2)] and expressed as z-scores [24]. Waist and hip circumferences were measured with a nonstretchable plastic tape measure according to standard methods [25]. Anthropometric measures were standardized at the annual PHACS meeting through training sessions conducted by a registered dietician who was experienced in anthropometry. The per cent

body fat was calculated from a total body dual-energy X-ray absorptiometry (DXA) scan performed on either a Lunar (General Electric Healthcare, Bucks, UK) or Hologic (Hologic Inc., Bedford,

MA) scanner according to standard methods [26]. Scans were sent to the Body Composition Analysis Center at Tufts University School of Medicine (Boston, MA, USA) for central analysis and standardization. Fasting serum levels of total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides, glucose and insulin were measured locally and in real-time at study entry for all HIV-infected children. Non-HDL cholesterol was calculated as the difference between total and HDL cholesterol. In HEU children, Palbociclib plasma lipid and lipoproteins were measured by standard methods at the Diabetes Research Institute Clinical Chemistry Laboratory at the University of Miami (Miami, FL), on a Cobas 6000 analyser (Roche Diagnostics, Indianapolis, IN) Acyl CoA dehydrogenase using the manufacturer’s reagents and procedures. The

homeostatic model assessment of insulin resistance (HOMA-IR) score was calculated: [fasting insulin (μU/mL) × fasting glucose (mmol/L)]/22.5 [27]. For HIV-infected children only, concurrent Centers for Disease Control and Prevention (CDC) paediatric HIV disease stage [28], absolute CD4 T-lymphocyte cell count, plasma HIV-1 RNA by quantitative polymerase chain reaction (PCR) (viral load) and ARV regimens were recorded. Fibrinogen and CRP were measured at a central laboratory by nephelometry on a Dade-Behring (Deerfield, IL) auto-analyser using the manufacturer’s reagents and instructions. Intra- and interassay coefficients of variation were 2.6 and 2.7%, respectively, for fibrinogen and 4.4 and 5.7%, respectively, for CRP. Adiponectin was measured using a double-antibody radioimmunoassay (Linco Research, St Charles, MO), with intra- and inter-assay coefficients of variation both <5%. CRP values >10 mg/dL were not used in the data analysis because high levels could be caused by intercurrent infection.

4f and h). A polyclonal antibody to flagella from B. bacilliformis (Scherer et al., 1993), which is closely related to A. felis, did not recognize Afipia flagellae, indicating substantial diversity in their flagella amino acid sequences. DNA was isolated and sequenced outward using primer Kan-2 FP01 for the transposon-flanking regions. We have obtained two sequences that prove an integration of the transposon in genes involved in flagella biosynthesis (Fig. 5). The sequence of mutant G4 (Fig. 4f) showed high similarities to FlhA, a part of the flagella export apparatus in different Sotrastaurin cell line bacteria species (Ghelardi et al., 2002; McMurry et al., 2004). This mutant was detected using nonpermeabilized cells

and CSD11, because the CSD11 target antigen (flagellin) did not appear on the bacterial cell surface due to an export defect. When the same screen was performed in the presence of sodium dodecyl sulphate (SDS) to permeabilize the bacterial cells, this mutant showed weak signals due to the accessibility of the flagellar antigen under these conditions and was therefore not detected (data not shown). In an SDS-polyacrylamide gel electrophoresis (PAGE) with bacterial lysate material, the signal was not intense enough to be detected (Fig. 4i). One possible reason could be the degradation of the protein when export is disturbed as shown for a flhA mutant of Bacillus thuringiensis (Ghelardi et

al., 2002). Such fragments might be too small for detection in standard Western-blotting experiments with SDS-PAGE, while they are detected using colony blots. Similar reasons probably caused the identification of a total of seven flagella-deficient JAK cancer mutants in a screen without SDS permeabilization, while in its presence none of these clones was identified (data not shown). The mutant D5 (Fig. 4g) likely codes for a defective flagellin gene, probably in the region corresponding to the protein’s C-terminus. This would explain why the flagellin is still detected by CSD11 antibody but the protein had a reduced molecular weight. Because of the ∼420 remaining amino acids before insertion of the transposon (Fig. 5a), the expected mass of the truncated flagellin would be about 40–45 kDa, which

is the mass of the observed truncated flagellin in Western blot (Fig. 4i). Because the C-terminus of flagellin is those well conserved and important for assembly of the flagellar filament (Beatson et al., 2006), a defect in this area can result in unstable shortened flagella, which were observed using immunofluorescence (Fig. 4g) as well as scanning electron microscopy (Fig. 4b). In summary, we provide evidence that we have developed a genetic system to mutagenize Afipia spp. and a suitable vector system for gene cloning in this genus. We further present the first mutant A. felis, in this case with defects in flagella biogenesis. The tools presented here will help to analyse the unusual phagosome biogenesis of A. felis in macrophages (Lührmann et al.

Salicylic acid, however, was not synthesized to any appreciable extent from chorismic acid by extracts prepared from any of the mutants grown similarly: ∼1 ng by CFEs from knockouts of trpE2, entC and entD as single mutants and 0.25 ng by entDtrpE2 as a double

mutant (Fig. 1). These very low conversions suggest that a combination of the gene products from trpE2, entC and entD or, probably and more likely, that all three genes play a role in the synthesis of salicylic acid from chorismic acid. To evaluate which genes are involved in the conversion of chorismic acid to isochorismic acid and then in the conversion of isochorismic acid to salicylic acid, the above experiment was modified such that isochorismic PF-01367338 acid was extracted before estimating salicylic acid and hence could confirm the involvement of trpE2, entC and entD in the stepwise conversion. Accordingly, the CFEs of each of the three single mutants were prepared. Each contained approximately 10 mg protein mL−1 and were incubated individually with chorismic acid as a substrate at 37 °C in a total volume of 2.3 mL (Marshall & Ratledge, 1971). After 1 h, the reaction was stopped with HCl and each mixture was extracted with ethyl acetate (see Materials and methods) to remove any isochorismic acid that had been formed. Each of these solvent extracts,

now in an aqueous buffer, was then divided into three equal aliquots CHIR99021 and each of these was placed in separate test tubes. For each batch of three solvent extracts, one was incubated without addition of CFE (control), and the other two were incubated with a CFE other than the one that had been used originally (Table 1). In other words, this was a cross-over biochemical reaction. The synthesis of salicylic acid occurred when CFEs from mutants of either entC or entD were used in the first reaction with chorismic acid as a substrate and followed by using the CFE of mutant trpE2 in the second reaction. The synthesis of salicylic acid was completely absent when a CFE of mutant trpE2 was used in the first reaction, irrespective

Adenosine of which CFE was used in the second reaction (Table 1). As salicylic acid is principally converted to mycobactin, with only about 5–10% being converted into carboxymycobactin (Ratledge & Ewing, 1996), we then studied the production of mycobactin in the knockout mutants. The wild type and the mutants of M. smegmatis were grown for 7 days in minimal medium under iron-deficient conditions (which are needed to maximize mycobactin formation) with and without salicylic acid added at 5 μg mL−1. The production of mycobactin by the mutants was drastically decreased in minimal medium compared with the wild-type strain (Fig. 2). However, when salicylic acid was included in the medium, the mutant cells had considerably more mycobactin than before, although the amounts were well below those in the wild-type strain (Table 2).

Salicylic acid, however, was not synthesized to any appreciable extent from chorismic acid by extracts prepared from any of the mutants grown similarly: ∼1 ng by CFEs from knockouts of trpE2, entC and entD as single mutants and 0.25 ng by entDtrpE2 as a double

mutant (Fig. 1). These very low conversions suggest that a combination of the gene products from trpE2, entC and entD or, probably and more likely, that all three genes play a role in the synthesis of salicylic acid from chorismic acid. To evaluate which genes are involved in the conversion of chorismic acid to isochorismic acid and then in the conversion of isochorismic acid to salicylic acid, the above experiment was modified such that isochorismic http://www.selleckchem.com/products/XAV-939.html acid was extracted before estimating salicylic acid and hence could confirm the involvement of trpE2, entC and entD in the stepwise conversion. Accordingly, the CFEs of each of the three single mutants were prepared. Each contained approximately 10 mg protein mL−1 and were incubated individually with chorismic acid as a substrate at 37 °C in a total volume of 2.3 mL (Marshall & Ratledge, 1971). After 1 h, the reaction was stopped with HCl and each mixture was extracted with ethyl acetate (see Materials and methods) to remove any isochorismic acid that had been formed. Each of these solvent extracts,

now in an aqueous buffer, was then divided into three equal aliquots learn more and each of these was placed in separate test tubes. For each batch of three solvent extracts, one was incubated without addition of CFE (control), and the other two were incubated with a CFE other than the one that had been used originally (Table 1). In other words, this was a cross-over biochemical reaction. The synthesis of salicylic acid occurred when CFEs from mutants of either entC or entD were used in the first reaction with chorismic acid as a substrate and followed by using the CFE of mutant trpE2 in the second reaction. The synthesis of salicylic acid was completely absent when a CFE of mutant trpE2 was used in the first reaction, irrespective

Rebamipide of which CFE was used in the second reaction (Table 1). As salicylic acid is principally converted to mycobactin, with only about 5–10% being converted into carboxymycobactin (Ratledge & Ewing, 1996), we then studied the production of mycobactin in the knockout mutants. The wild type and the mutants of M. smegmatis were grown for 7 days in minimal medium under iron-deficient conditions (which are needed to maximize mycobactin formation) with and without salicylic acid added at 5 μg mL−1. The production of mycobactin by the mutants was drastically decreased in minimal medium compared with the wild-type strain (Fig. 2). However, when salicylic acid was included in the medium, the mutant cells had considerably more mycobactin than before, although the amounts were well below those in the wild-type strain (Table 2).