Divergent pathways for δ-aminolevulinic acid synthesis in two species of Arthrobacter

Abstract

Secretion of coproporphyrin III by suspensions ofArthrobacter phorogonimos and A. globtjiwmis facilitated analysis of the paths of synthesis of &aminolevulinic acid, the precursor of tetrapyrroles. Sensitivity of coproporphyrin accumulation to gabaculine and incorporation of 14C from [I-"C]glutamate indicated that suspensions of A. photogonimos synthesized S-aminolevulinic acid from glutamate by the widespread C5 pathway. In contrast, A. glob@-mis cells switdhed from predominantly the C5 pathway for d-aminolevulinic acid synthesis in early exponential phase cultures to Gamitiolevulinic acid synthase in stationary phase cultures.

Occurrence of Two 5-Aminolevulinate Biosynthetic Pathways in Streptomyces nodosus subsp. asukaensis Is Linked with the Production of Asukamycin

“…The steady state of the gtr transcript remained fairly constant throughout the whole growth period of S. nodosus and differed somewhat from that of S. coelicolor, which showed a slight increase in specific mRNA concentration in the stationary phase. Accordingly, the possibility cannot be excluded that in the later growth stages of S. nodosus, a part of ALA from the Shemin pathway is utilized in the porphyrin biosynthetic route, as in the case of A. globiformis (57). Consistently, the hemA-asuA gene complemented the gtr mutation in the S. coelicolor MIP14 strain only when its native promoter was replaced with ermE*.…”

“…The ALAS, representing the Shemin pathway, is encoded by the nuclear gene and is located in mitochondria, where it synthesizes the precursor for the heme biosynthesis. So far, the existence of two functional ALA pathways in one prokaryotic organism has been suggested only in Arthrobacter globiformis, where cells switch from the C 5 pathway (predominant in early exponential phase cultures) to the Shemin pathway in stationary phase cultures (57). ALA is also synthesized by Rhodobacter sphaeroides in two ways; however, in these cases synthesis is performed by two ALAS isozymes, products of hemA and hemT genes, which are localized to different chromosomes (35,52).…”

Bacteria belonging to the extremely versatile genus Arthrobacter as novel source of natural pigments with extended hue range

“…Lately, two new members from the genus Arthrobacter, A. photogonimos and A. aurescens, have been found to produce coproporphyrin (Scharf, Mamet, Zimmels, Kimchie, & Schoenfeld, 1994;Yang & Hoober, 1995). Following the isolation and the characterization of A. aurescens, the strain A. aurescens RS-2, was found to secrete a large amount of coproporphyrin III in response to aluminum, if present in cultures.…”

Recent Progress in Porphyrin and Chlorophyll Biosynthesis

“…5-Aminolevulinate synthase is also found in nonphotosynthetic bacteria such as Bradyrhizobium japonicum (38), Rhizobium melilotii (39), Spirillum itersonii, Pseudomonas den-itr@cans, Propionibacter shermanii and Streptomyces xanthochromogenus (1 0,22,23). 5-Aminolevulinate-synthase activity was recently demonstrated in Arthrobacter globiformis but not in Arthrobacter photogonimos where the Cs pathway operates (see below) (40).…”

“…A recent report demonstrates the coexistence of the Cs and ALA-synthase pathways also in a prokaryote, A. globqormis: the Cs and ALA-synthase pathways were demonstrated during exponential and stationary phases of growth, respectively (40). Only the C5 pathway was detected in A. photogonimos (40).…”