Extracellular acid proteases from Neurospora crassa

Journal Article · Tue Jun 01 04:00:00 EDT 1982 · J. Bacteriol.; (United States)

OSTI ID:6706473

Lindberg, R A ^[1]; Rhodes, W G; Eirich, L D; Drucker, H

---

1. Pacific Northwest Lab., Richland, WA

Three electrophoretically distinct acid proteases appear in culture filtrates of Neurospora crassa. Like the previously investigated alkaline and neutral proteases, these enzymes require induction by an exogenous protein. But in contrast to alkaline and neutral proteases, which are synthesized and secreted in response to limitation of any one of three nutrilites (carbon, nitrogen or sulfur), extracellular elaboration of the acidic proteases is more specifically a function of the missing nutrilite. AcP, a pepstatin-inhibitable enzyme similar to other fungal carboxyl proteases, was secreted in large amounts when protein was the sole source of sulfur. Only trace amounts were secreted when nitrogen was the limiting nutrilite, and it was undetectable under carbon limitation. M-1, a chelator-sensitive protease, was secreted when nitrogen or carbon was limiting. M-2, also chelator sensitive, was present only when nitrogen or sulfur was limiting. The evidence presented suggests that the differential regulation of the acidic proteases with respect to nutrilite deprivation may not occur at the level of transcription. AcP and M-2 were partially purified from nitrogen-derepressed cultures by ultrafiltration, cation-exchange chromatography, and gel filtration. AcP has a molecular weight of 66,000, is stable from pH 3.0 to 6.0, and is optimally active toward bovine serum albumin at pH 4.0. M-2 has a molecular weight of 18,000, is stable from pH 1.6 to 5.5, and has optimal activity at pH 4.5.

• DOE Contract Number: AC06-76RL01830
• OSTI ID: 6706473
• Journal Information: J. Bacteriol.; (United States), Journal Name: J. Bacteriol.; (United States) Vol. 150:3; ISSN JOBAA
• Country of Publication: United States
• Language: English

Related Subjects

550200* -- Biochemistry
550700 -- Microbiology
59 BASIC BIOLOGICAL SCIENCES
CHEMICAL PROPERTIES
CHROMATOGRAPHY
DATA
ELEMENTS
ENZYME ACTIVITY
ENZYMES
EXPERIMENTAL DATA
FILTRATION
FUNGI
HYDROLASES
INFORMATION
MOLECULAR WEIGHT
NEUROSPORA
NITROGEN
NONMETALS
NUMERICAL DATA
ORGANIC COMPOUNDS
PEPTIDE HYDROLASES
PH VALUE
PHYSICAL PROPERTIES
PLANTS
PROTEINS
PURIFICATION
SEPARATION PROCESSES
SUBSTRATES
ULTRAFILTRATION